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" This is a compreliensive and ■well-written book o-n the subject of which it treats. 
 The author's professional standing and large experience justify the publication of 
 his views with regard to the employment of plastic materials in the treatment of 
 decay occurring in teeth. His remarks concerning the employment of gold as a 
 stopping in decay of teeth which are below the average development of structure, 
 or in which, by the inaccessible position of the cavity, a perfect gold stopping 
 cannot be insured, are well worthy of careful perusal. The author states emphati- 
 cally that many teeth are lost owing to the injudicious use of gold. Such a 
 statement, coming from one who has been nurtured in the land of ' gold stopping,' 
 would scarcely have been made without mature observation and calm reflection. 
 We are certainly much inclined to his views, and are quite in accord with him in 
 maintaining that the chief duty of the dental surgeon should be to preserve the 
 dental tissues, rather than to inquire at how early a date his patient may need those 
 artificial substitutes which at the best are but imitations of their natural predecessors. 
 The work is well arranged and admirably illustrated."— Xondon Lancet, 
 
 "This volume is an octavo, printed on excellent paper, with wide margins, in a 
 good, clear-faced type, and is well and tastefully bound, making altogether a very 
 fine appearance and an exceptionally agreeable book to read. . . . Whatever 
 may be thought of Dr. Flagg's theories or practice, he has evidently made an honest 
 and earnest effort to give the benefit of his experience to the profession. The 
 teaching is so explicit that none need complain that there is any want of definite- 
 ness in it." — Dental Cosmos, April, 1881. 
 
 " A less courageous man than Dr. Flagg would have hesitated before presenting 
 to the profession a book of this character — not, however, that the character of the 
 book is bad. Dr. Flagg has taken the plastic bull by the horns, and forced said bovine 
 to the front, and sustained him in that position by a remarkably clear and precisely 
 written volume. . . . If plastic materials are used at all, they should be prepared 
 ■ and inserted in the most precise and careful manner, and Dr. Flagg characteristically 
 shows how this can be done." — Dental Advertiser. 
 
 " Dr. Flagg's treatise has great literary merit. It is logical, forcible, and so clear 
 in its statements that scientific facts, theories, and methods are made plain to unscien- 
 tific readers. But its greatest merit is that it illustrates the second great advance 
 in the progress of dentistry, and that it gives expression to principles and methods 
 of investigation, which, if followed in the future with the same intelligent enthu- 
 siasm, must produ.ee vezy important lesults." — PMladelpMo, Inquirer. 
 
PLASTICS 
 
 A^^) 
 
 PLASTIC FILLIITG; 
 
 AS PEKTAIXIXG TO THE 
 
 FILLIJs'G OF ALL CAVITIES OF DECAY IX TEETH 
 BELOW MEDIUM IN STEUCTUEE, 
 
 DIFFICULT AND INACCESSIBLE CAVITIES 
 IN TEETH OF ALL GEADES OF STEUCTUEE. 
 
 BY 
 
 J. FOSTER FLAGG, D.D.S., 
 
 PROFESSOR OF DEXTAL PATHOLOGT AXD THERAPETJTICS IN 
 PHILADELPHIA DEXTAL COLLEGE. 
 
 WITH ILLUSTBATIOJSrS. 
 
 SECOND EDITION, REVISED. 
 
 PHILADELPHIA: 
 
 1883. 
 
 ^^ 
 

 Copyright. 
 J. FOSTER FLAGG. 
 
 1883. 
 
 ALL EIGHTS EKSEEVED. 
 
 gTEEEOTYPED BY J. FAOAN & SON, PHILADELPHIA. 
 PRINTED BY SHERMAN & CO. 
 
TO 
 
 THE SCIENTIFIC, lETALLURGIC, AND -DENTAL SECTIONS 
 
 "NEW DEPARTURE CORPS," 
 
 THIS MONOGEAPH 
 
 IS INSCRIBED, AS A TESTIMONIAL 
 
 OF INDIVIDUAL INDEBTEDNESS, 
 
 OF SINCERE RESPECT, 
 
 AND OF KIND REGARD. 
 
PREFATORY. 
 
 TN explanation of the occasionally desultory arrangement 
 of the matter in these pages, and of some of the peculi- 
 arities of composition, I would say that the " Articles " were 
 originally intended for magazine contributions, but, in evo- 
 lution, the statements which I decided to make, the infor- 
 mation which I desired to give, and the deductions which 
 would necessarily have to be drawn, were such as I could 
 not ask any magazine of extensive circulation, with exten- 
 sive business interests, to publish. I have therefore con- 
 cluded to offer them in this form that I might, for the 
 good of my profession — as I hope and as I trust — dis- 
 seminate, in all its integrity, the results of that work which 
 has been done by the " ]^ew Departure Corps" under its 
 motto, " Truth, without fear and without favor." 
 
 J. FosTEE Flagg. 
 
 Philadelphia, 106 N. 11th St. 
 
CONTENTS. 
 
 INTRODUCTORY. 
 
 PAGE 
 
 Difference in basal principles wliich exists between the Schools of Gold and 
 
 Plastic Dentistry 11-18 
 
 ARTICLE I. 
 
 PLASTIC FILLING. 
 History of the work upon the " Systematic Development of Plastic Filling " 19-23 
 
 ARTICLE. II. 
 
 AMALGAM. 
 
 Silver Paste ; Royal Mineral Succedaneum ; Action of the American Society 
 
 of Dental Surgeons ; Dissolution of that Association .... 24-29 
 
 ARTICLE III. 
 
 A3IALGAM.—Cont.inued. 
 
 Facts worthy of consideration ; Prof Elisha Townsend's sanction of amal- 
 gam ; His acceptance and advocacy of proposed improvements in alloy 
 and making of amalgam ; Action of the representative men of the pro- 
 fession ; Professor Townsend's " recantation ; " The three basal positions 
 in connection with amalgam which decided me in continuing work, not- 
 withstanding my leader's " recantation ; " Conclusions reached by five 
 years of experiment and observation 29-36 
 
 ARTICLE IV. 
 
 AMALGA3L— Continued. 
 
 From 1861 to 1875 ; Change of formula; Adoption of "lining; " December, 
 1874, Meeting of New York Odontological Society ; Metallurgic associ- 
 ation with Messrs. Du Bois and Eckfeldt ; Comments upon paper of Pro- 
 fessor Hitchcock ; Comparison of Analyses of Amalgam Alloys ; Remarks 
 on " Gold and Platina " alloys ; Remarks on " advanced collegiate instruc- 
 tion" 37-42 
 
 ARTICLE V. 
 
 ATTRIBUTES OF METALS USED FOB AMALGAM ALLOYS. 
 
 Definitions of " alloy " and " amalgam ; " Theory of the formation of amal- 
 gams ; Metals used in amalgam alloys ; Silver ; Tin ; Copper ; Gold ; 
 
 Antimony; Zinc; Cadmium; Platinum 43-60 
 
 vi 
 
CONTENTS. Vll 
 
 ARTICLE VI. 
 
 THE MAKING OF AMALGAM ALLOYS. 
 
 "Accepted" methods given by different instructors; The completely differ- 
 ent method of the " New Departure " metal workers ; Cutting of alloy 
 into " grains," " tilings," or " a kind of powder ; " Inferiority of" fresh " 
 cut alloy; Superiority of "aged" alloy filings; Qualitative Testing of 
 Amalgam Alloys 61-66 
 
 ARTICLE VIL 
 
 TESTS FOR AMALGAM. 
 
 Quality test ; Shrinkage test ; Color test ; Edge-strength test ; Tooth-con- 
 serving test . 67-80 
 
 ARTICLE VIII. 
 
 PREPARATION OF CAVITIES. 
 
 Comparison of preparations for gold, with preparations for amalgam ; Effect 
 
 of amalgam upon contiguous dentine 80-84 
 
 ARTICLE IX. 
 
 THE MAKING OF AMALGAM. 
 
 Former methods ; Remarks on alcoholic " washing ; " Mortar-make ; 
 Weighing for proportions; Ground -glass mortar and pestle; The 
 method of rubbing ; Method of kneading ; The forming of a " button ; " 84-92 
 
 ARTICLE X. 
 
 INSTRUMENTS FOR THE INSERTION OF AMALGAM FILLINGS. 
 
 Description of instruments ; Round ends; Flat ends; Trimmers or Sepa- 
 rators; Spatula; Elliott's " Loadstone " amalgam -carrier and plugger; 
 Elliott's amalgam carrier ; Chase's amalgam carrier ; Fry's amalgam 
 carrier; Mullett's " Amalgam Director ; " Curious and useless appli- 
 ances . 92-99 
 
 ARTICLE XI. 
 
 THE INSERTION OF AMALGAM FILLINGS. 
 
 Necessity for acquirement of manipulation by nearly every dentist, from 
 the marked difference in physical characteristics between " accepted " 
 amalgams, and those offered by the " New Departure ; " Present di- 
 vision of amalgams; Submarine; Usual; Contouring; Front Tooth; 
 Facing; Manipulations for insertion of amalgam mass; Wafering; 
 Shaping; Smoothing; Finishing; Whitening; Subsequent burnish- 
 ing, if indicated ; Remarks upon burnishing the edges of partially-set 
 amalgam fillings 99-107 
 
Vlll CONTENTS. 
 
 ARTICLE XII. 
 
 GENERAL CONSIDERATIONS PERTAINING TO AMALGAM. 
 
 1. Local effects; 2. Systemic effects ; 3. Possibilifies ; First. Local Effects. — 
 Discoloration of filling and tooth ; Induction of galvanic electricity by 
 contact with other metal ; Shock ; Metallic salivation ; Bad taste ; Irri- 
 tation of fauces, throat, and larynx ; Pulp-devitalizati'on ; Periodon- 
 titis ; Alveolar abscess ; Exostosis ; Necrosis. 
 
 Second. Systemic Effects. — Proceedings of Pennsylvania Association 
 of Dental Surgeons, April, 1861 ; Testimony of members adverse to 
 mercurial ptyalism, mercurial necrosis, etc. ; My own opinion regard- 
 ing mercurialization from amalgam fillings. 
 
 Third. Fossibilities. — Possibilities of amalgam are greater than those 
 of all other Jill ing materials combined ; Comparison of the working of 
 gold with that of amalgam ; Ordinary cavities ; Large cavities ; Enor- 
 mous cavities ; Entire crowns ; Attaching gold crowns by amalgam ; 
 Replacing natural crowns ; Attaching natural crowns ; Pivoting teeth ; 
 Bonwill pivot; Gates Pivot; Flagg pivot; '' Guarding " or repairing 
 gold fillings, and refilling cavities from which gold fillings have been 
 lost, in teeth which still contain gold fillings; Bi-metallic fillings; 
 Therapeutic value of these; Amalgam teeth on gold plates ; Fractures 
 of teeth from fillings either of gold or amalgam ; Split teeth ; Per- 
 forated teeth ; Loose and divided roots ; The dividing line between the 
 impossibilities of gold work and the continued easy possibilities of 
 amalgam work ; The comfort from plastics 107-141 
 
 ARTICLE XIII. 
 
 GUTTA-PERCHA. 
 
 Hill's stopping ; Gutta-percha and Oxide of Zinc Stoppings ; Leakage of 
 gutta-percha fillings; "Low-heat" gutta-percha; "Medium heat;" 
 "High heat;" E,ed base-plate ; Oil-pad; Modes of heating gutta-percha 
 "filling materials ; Methods of heating instruments ; Considerations per- 
 taining to preparation of cavities for gutta-percha fillings ; The intro- 
 duction of fillings ; Finishing fillings ; Tests for gutta-percha stopping ; 
 Heat-test; Fire-test; The making of gutta-percha stopping; Dura- 
 bility of gutta-percha fillings; Cavities in which the use of gutta- 
 percha alone is indicated ; The varied uses of gutta-percha stoppings 141-150 
 
 ARTICLE XIV. 
 
 OXY-CHLORIDE OF ZINC. 
 
 Sorel cement; Uses of oxy-chloride of zinc; "Talcing" fillings; Oxy- 
 chloride not a filling material; Oxy-chloride a complete "liner;" 
 Failure of oxy-chloride from attrition ; Failure of oxy-chloride from 
 cervical disintegration ; The making of oxy-chloride powder ; The 
 making of the fluid ; The mixing of the materials for filling ; Method 
 of lining cavities ; Results attained by the use of oxy-chloride ; Re- 
 marks in relation to " combination " fillings ; " Whitening " teeth by 
 the use of oxy-chloride 151-160 
 
CONTENTS. 
 
 IX 
 
 ARTICLE XV. 
 
 OXY-SULPHATE OF ZINC. 
 
 Jfot a filling material, but eminently useful as an adjunct to plastic fillings ; 
 The making of oxy-sulphate powder ; The making of oxy-sulphate 
 fluid ; Oxy-sulphate as a pulp-capper ; Its mixing ; Capping by spat- 
 
 ula placing; Capping by pellet placing 
 
 160-162 
 
 ARTICLE XVI. 
 
 ZINC-PHOSPHA TE. 
 
 Ostermann's formula; The zinc-phosphates of the present; The oxy-phos- 
 phates ; The making of zinc-phosphate powder; Tests for distinguish- 
 ing it from oxy-phosphate powder (calcined oxide of zinc) ; Remarks 
 on oxy-phosphate and zinc-phosphate fluids, syrups, and ciystals; Mix- 
 ing zinc-phosphate ; Working tests for grading a " good " zinc-phos- 
 phate material ; Working tests foe, grading a "poor" zinc-phosphate; 
 Directions for using zinc-phos25hate ; Varnish recipes ; Final manip- 
 ulative suggestions ; Conclusions as to value of zinc-phosphate cement 162-174 
 
 ARTICLE XVII. 
 
 TEMPORARY STOPPING. 
 
 Directions for making 
 
 174 
 
 ARTICLE XVIII. 
 
 TECHNICALITIES. 
 
 Ageing . 
 Bulging . 
 Buflering ; Capping ; 
 
 175 
 176 
 
 Cold-Solder- 
 
 177 
 179 
 180 
 
 Mixing . . . . . .191 
 
 Pelleting; Rubbing . . .193 
 Setting . . . . ... 195 
 
 Softening 197 
 
 Shrinkage 198 
 
 Tapping; Testing . . , .199 
 
 Trimming 202 
 
 Trunnioning ; Wafering . . 203 
 
 Washing; Weighing . . .204 
 
 AVhitening 206 
 
 Conclusion 207 
 
 Appendix 208 
 
 Crevicing 
 Domeing; Facing . 
 
 Frotting 182 
 
 Guarding 183 
 
 Heating 189 
 
 Lining 190 
 
Pusfeatiflw. 
 
 MONOGEAM, N. D. C 
 
 MiXEK 
 
 Index Micrometer 
 
 "Shrinkage" Microscope 
 Edge-Strength Tester and Ingot Matrix 
 Mortar, Pestle, and Mercury Holder 
 Amalgam Instruments .... 
 
 Amalgam Carriers, etc 
 
 Gutta-Percha Warmer and Tool-Heater 
 Gutta-Percha Heat-Tester 
 Frotting Tester . . . » . 
 Wafering Pliers ...... 
 
 FA6K 
 
 . iii 
 
 opposite 65 
 
 74 
 
 75 
 
 77 
 
 90 
 
 93 
 
 98 
 
 144 
 
 147 
 
 183 
 
 204 
 
":::::t:::::;:-»"-'>- 
 
 '■ • . . _ P-lCiK 
 
 <yp}y(>»ite 128 
 " 145 
 
 PLASTICS 
 
 AND 
 
 PLASTIC FILLINa 
 
 INTEODUCTOEY. 
 
 BEFOEE entering upon considerations pertaining to the his- 
 toric, analytic, utilizing, and manipulative detail of our 
 subject, I feel desirous that the thoughts of my readers should 
 De so directed as that there shall be, at once, a recognition of 
 the great fundamental differences in basal principles and prac- 
 tice which exist between the Schools of Grold and Plastic Den- 
 tistry. 
 
 As facts in relation to present methods and results are accu- 
 mulating, I am the more impressed with the growing need for 
 the uprooting of that tendency in dental teachings and practice 
 which has, thus far, resulted in such waste of time, energy, 
 strength, money, and teeth, and which still, in some sort, holds 
 sway at the gatherings of the "wise men." 
 
 The idea of pounding piece after piece of gold into some 
 inaccessible pocket, far below the gum, in an " annex " to a 
 cavitjr almost into the pulp, on the distal face of a lower 
 molar of poor structure, and calling it "the highest attain- 
 ment of first-class dentistry," is, to me, something incompre- 
 hensible ! It is but trifling with the dignity, the broad ability, 
 the glorious possibility, of our profession. ISTor is this an 
 overdrawn picture; it is preciselj^ what is yet done — done 
 "by and with the advice and consent of the Senate," and it is 
 
 11 
 
12 PLASTICS AND PLASTIC FILLING. 
 
 truly an imposition upon patients and upon tlie younger den- 
 tists, inflicted in tlie name of science and of art. 
 
 The depth and the breadth of the work to which I have 
 been called impresses me most earnestly as I view more and 
 more clearly the vast difference between " Gold-work," regard- 
 ing that as one school of dentistry, and " Plastics," regarding 
 that as another school of dentistr}^ 
 
 Outwardly, the two schools are very different even to the 
 most casual observer, but in proportion as one is educated 
 in both, this external difference becomes even more tangibly 
 apparent ; the materials are different ; the appliances are dif- 
 ferent; the methods are different; the instruments are differ- 
 ent; the attempts are different; the possibilities are different, 
 and the results are different. 
 
 The time has gone by when to this last assertion the " gold- 
 workers" can say, with a palpably implied tone of superiority, 
 "Yes, the results are, indeed, widely different," for the people 
 are trumpeting loudly their stories of heart-sickening failures 
 and wholesale loss of teeth. The mouths of a fearful propor- 
 tion of this generation reveal only too glaringly the peculiar 
 curve of " porcelain teeth mounted on vulcanite," and the de- 
 mand is for something far different from that which has here- 
 tofore been given them as " dentistry." 
 
 But great as are the external differences between the " gold- 
 workers' " practice of dentistry and its practice from the 
 "plastic" standpoint, the internal differences are vastly greater. 
 The ideas of the two kinds of practice flow in two channels, 
 than which no two could be more distinct. The thoughts 
 which govern work in the two kinds of practice are constantly 
 almost diametrically antagonistic, and are never ^ in any degree, 
 sympathetic. 
 
 The niinutise of '■^plastics " is an unhnown thing to the gold- 
 ivorher. It consists of special knowledge in regard to much 
 which is only known to him as a mass of vague generalities; 
 ichile the '■'■ways and m,eans''^ of the worker in plastics are 
 viewed askance by the gold-worker as a series of shiftless devices 
 promotive of slovenly results. 
 
 The minuiise of ^''gold-work'''' is utterly ignored hy the worker 
 of ''' jjlastics^'' and for such " ivays and means " as he sees the 
 
INTRODUCTORY. 13 
 
 gold-tvorher resort to in ^^ difficult cases,''^ the worJcer of plastics 
 has a shuddering horror ! 
 
 The first view of any case in practice, as seen from the two 
 standpoints, is provocative of such different impressions upon 
 the two practitioners as renders it impossible that the one 
 shonld have any conception of the effect made upon the other; 
 and only he who is conversant with both schools can, in full 
 degree, appreciate this. 
 
 Take, for instance, in a perfect arch, a lower second molar ; 
 soft structure; largely decayed distalty and buccally; the decay 
 extending deep below the gum in both directions and running 
 out to feather-edges ; with frail, overhanging cavity walls me- 
 sially and lingually ; the pulp almost exposed ; the patient, a 
 lady of nervo-bilious temperament, middle-aged, a sufferer from 
 congestion of the liver, and overtaxed nervously. 
 
 What is the first thought of the "gold-worker"? It is, How 
 shall I get a good^ solid, gold filling into this cavity? 
 
 What is the first thought of the' "worker in plastics"? It 
 is. What is it hest that I should fill this cavity with ? 
 
 Next comes the cavity preparation. The thoughts of the gold- 
 worker are concentrated upon the making of free access for the 
 introduction and packing of his gold ; upon the securing of 
 strong, smooth edges ; upon the making of retaining points ; 
 upon the removal of all decay, except such as would endanger 
 the pulp, that his gold may have a solid foundation to rest 
 upon, and that he may be able to introduce a filling which will 
 not leak; upon the possibility of "capping," — thinking of "con- 
 duction" of filling material, — and upon the squaring and the 
 grooving of the walls at feather-edges. 
 
 The thoughts of the worker in "plastics" are upon the con- 
 servation of enamel ; the spheroiding of cavity contour ; the 
 conservation of decay, — within the bounds of filling integrity, — 
 hardly bestowing a thought upon the pulp, and certainly no 
 thought upon pulp irritation from "conduction;" choosing, men- 
 tally, a filling possessed of " edge-strength " in view of feather- 
 edge to cavity; selecting his most trustworthy "submarine" 
 in view of depth of cavity below the gum; projecting a "com- 
 bination filling" which shall be composed of four metal amal- 
 gam — mercury, silver, tin, and copper; five metal amalgam — 
 
14 PLASTICS AND PLASTIC FILLING. 
 
 mercury, silver, tin, copper, and gold. Good gutta-percbas, — 
 red or white "low heat" and white "medium heat," — each fill- 
 ing material used in its proper place for the attaining of some 
 specific result ; and thus, according to his ideas, best securing 
 against recurrence of decay ; best affording good maintenance 
 of color and contour for resistance in mastication; and best 
 securing that uninterrupted pulp action which shall not only 
 preserve the integrity of the organ, but shall eventuate in re- 
 calcification of the remaining substratum of decalcified dentine. 
 
 Next follows the introduction of the filling. Here the seri- 
 ous labor of the gold-worker begins. He is an earnest, con- 
 scientious man ; he is an eminently skilful manipulator ; he 
 glories in his work ; his whole thought must now be concen- 
 trated upon the introduction of his filling ; any interference 
 with this precludes the possibility of success. 
 
 As a necessary prelude, the decayed tooth and the adjoining 
 teeth must be placed "under rubber." The work of adjusting' 
 the rubber- dam, in such a case as this, is one requiring much 
 knowledge, much patience, and much dexterity ; knowledge of 
 fitness and quality of rubber- dam, knowledge of punches and 
 their using, knowledge of clamps and clamp-forceps ; patience 
 under difficulty, patience oftentimes under repeated tearing 
 and slipping of the dam, patience under remonstrance at in- 
 fliction, patience under failure until success is attained ; dex- 
 terity in forcing clamps below the gum, dexterity in passing 
 rubber over clamps and over and between the teeth, dexterity 
 in placing and securing retaining ligatures. 
 
 All this work is very exhausting both to patient and opera- 
 tor; and it is, therefore, under conditions trying alike to mind 
 and bod}^ that the difficult task of the introduction of the fill- 
 ing is, at last, commenced. 
 
 Then comes a work of hours — two, three, it may be four — 
 in such a cavity as this. Whether it be of pellets, rope, or cyl- 
 inders ; whether it be of soft gold or cohesive ; whether it be 
 by hand-pressure or with mallet, — automatic, hand, engine, or 
 electric, — it is, by any means, in any way, a ■famous piece of 
 work. It is a work which can be hest done by not more than 
 one worker in a thousand ; a work which can be well done by 
 not more than one worker in a hundred ; a work which is not 
 
INTRODUCTORY. 15 
 
 reasonably well done by more than one worker in ten; and yet 
 a work wliicli is attempted in gold-ioorhing dentistry hy nine 
 workmen out of ten. 
 
 And during all the progress of this work, what are the 
 thoughts of the gold-worker? First, his thoughts are on the 
 choosing of his gold. Shall it be "Abbey's," "Globe," or "Ash- 
 mead's " ? Shall it be " Morgan's " or " Watt's Crystal " ? Next 
 his thoughts are on its preparation. He revels in the beauti- 
 ful. All his ideas are aesthetic. This is the "power" of such 
 gold work ; its strength is in its beauty^ and in the beauty of 
 its surroundings, and it must be recognized as possessing it ; 
 so he deftly handles his "crystal" as he picks off little mor- 
 sels, or folds his golden ribbons and cuts them into pieces, or 
 inrolls pellets, or twists sheets into ropes, all laid on skins of 
 kid or dropped on velvet cushions. 
 
 This being done, he thinks of final "warm-air" drying; and 
 next on the successful filling of the first retaining point ; and 
 then on the successful filling of the second retaining point. 
 Then his thoughts are upon the connecting of these two fill- 
 ings by a "first layer" of gold; and all this is at the "vulner- 
 able spot," at the disto-cervical edge. Not a piece must move ; 
 not a piece must miss its " weld ;" not a piece but must be 
 placed with that tension of accuracy which is so well known to 
 those of us who have been repeatedly prostrated under its de- 
 pressing influence, or the loorh will ^'■fail from defective manip- 
 ulation.'''' 
 
 It is just here that relief is sought by the gold-worker in 
 the possibilities of soft foil pellets and hand pressure ; and it 
 is upon the respective merits of soft gold and cohesive, in this 
 connection, that discussion has been going on for thirty years ; 
 the experiences of to-day are those of a quarter of a century 
 since ; the arguments and assertions of then are those of noio. 
 The subject has been hammered at until it is utterly attenu- 
 ated ; and in its gossamer-like thinness it is hammered at with 
 undiminished vehemence; so it is evident that the gold-worker 
 regards it as worthy of much thought. 
 
 The records of the last meeting of the American Dental 
 Association prove that no conclusion upon this point has been 
 reached, so that nothing definite can here be thought of by the 
 
16 PLASTICS AND PJLASTIC FILLING. 
 
 gold-worker ; biit by either mode tlie filling gradually grows ; 
 pellet is added to pellet, or fold after fold of rope is inserted, 
 or piece to piece is united, until finally the thought of the gold- 
 worker is, the gold is all in. 
 
 Next come the thoughts of finishing ; and this is also a pro- 
 longed task. Thoughts of files and burrs and stones ; thoughts 
 of corundum tape, pumice and tutty powder ; thoughts of bur- 
 nishers, flat, round, and ball ; thoughts of the beaatiful, lus- ; 
 tr'ous soap polish. 
 
 And in this work, as " hand, responsive to the thought," de- 
 velops, step by step, the " elegant conception," at last 'tis fin- 
 ished ; and some of the final thoughts are, truthfully, that " it 
 is perfectly magnificent;" that "it is evidence of exceeding 
 skill;" that "it is artistic." 
 
 To all this the worker in plastics says, Amen ! But others 
 of the final thoughts are, that "it is the test that could be 
 done ;" that " it is a proof of superiority as a dentist ;" that 
 " it is the most durable as a preserver of the tooth." 
 
 To these thoughts the worker in plastics does not say, Amen ! 
 
 He thinks, "I would not like to have that kind of thing done 
 to my tooth." "It certainly does prove that the gentleman is a 
 superior tooth -jeweller ; but I do not yet exactly recognize the 
 dental superiority.''^ And he next thinks of the teeth of that 
 kind which he has seen in which fillings of amalgam and gutta- 
 percha, SO COMFORTABLY INTRODUCED, have done ten years of 
 service, and bid fair to do years of service yet, in which just 
 such beautifully polished jewels had failed in from three to 
 eight years ; and if the gutta-percha is worn and cupped, and 
 if the amalgam is discolored, he feels toward them as he would 
 toward a stalwart old negro who had carried him safely over a 
 roaring river, — he views leniently the scars and farrows wrought 
 by time and exposure, and even forgives the fellow for having 
 a black skin! 
 
 As with the gold-worker, so with the worker in plastics. 
 After the preparation of the cavity, next comes the introduction 
 of the filling ; but with what different feelings and thoughts 
 does he come to the work. Selecting one of his thinnest sepa- 
 rating-slides he bends it to the desired shape, adapting it as a 
 broad clasp to the wisdom-tooth, with the outspoken thought, 
 
INTRODUCTORY. 17 
 
 " it will be less inflictive to withdraw a separating-slide than to 
 cut a separation between the filling and the adjoining tooth 
 with the cavity so deep under the gum ;" and then, drying the 
 cavity with bibulous paper, prepares for the introducing of his 
 material by simply pressing into the cavity pellets of cotton 
 moistened with oil of cloves, with just sufficient force to push 
 aside the gum ; he next selects his " submarine " alloy, with 
 thoughts of the requirements and knowledge of its compo- 
 sition and proportions ; he recognizes its liability to discolor, 
 but thinks of the tooth-saving effect of discoloration ; he rec- 
 ognizes the difficulties with which he has to contend, and thinks 
 cheerfully, both for himself and the patient, of the facility with 
 which, by his mode of practice, he will overcome them. And 
 with these thoughts he has weighed and made his material; 
 and now, removing the cotton pellets and again drying the 
 cavity, proceeds dexterously with the insertion of the lower 
 stratum of his filHng. With the " rough trimming " of his 
 work, his thought is " with what ease and celerity has this so- 
 called difficult operation been transformed into one of perfect 
 simplicity;" and with the remark that "it will now have to 
 wait for fifteen or twenty minutes," he proceeds with another 
 preparation or, for the few minutes, dismisses the patient. In 
 due time he removes his " slide," does what little finishing 
 trimming may be required, and then proceeds to place the 
 tooth "under rubber." He has no thoughts of clamps or 
 clamp-forceps ; he has but little, if any, thought of ligatures ; 
 he has removed everything that makes the placing of the rubber 
 a trying, difficult, and painful thing to the gold-worker and his 
 patient ; and thus, having punched three or four holes, his be- 
 ginning, instead of being the forcing of a clamp far below the 
 gum, — an operation which must be felt once to be appreciated, — 
 is the easy slipping of the dam over the bicuspids, and the al- 
 most equally easy successive damming of the molars ; he thinks, 
 with much inward satisfaction, that the rubber does not have to 
 go below the gum, and that, if a ligature is needed, it can be 
 placed with comfort to the patient. 
 
 Then his work may be considered practically done ; for, with 
 the cavity perfectly dry, the manipulation of " plastics " is sure 
 and easy ; the low-heat gutta-percha adheres to the softened 
 2 
 
18 PLASTICS AND PLASTIC FILLING. 
 
 dentine, covering the pnlp with a degree of heat whicTi is -un- 
 noticed even by that sensitive organism ; the quick-setting 
 alloy, of good color test, is rapidly and e'fiectively placed in 
 position without a disturbing thought of "flaking," "missing 
 weld," or "loosening of the filling at the vulnerable spot," and 
 the final finishing on the buccal face with the " medium " gutta- 
 percha completes a filling which to the worker in plastics sug- 
 gests a long train of satisfied thoughts as to its acceptable 
 introduction ; its happy meeting of varied requirements ; its 
 presentable, tooth-like appearance, and its probable value as a 
 durable, pulp-saving, tooth-saving, comfort-giving operation. 
 
AETICLE I. 
 ^ PLASTIC FILLING. 
 
 PEEMISIISrG- that the decided advantages wliicTi would accrue 
 from a gradually increasing employment of plastic filling 
 materials in connection with efforts for the saving of teeth, lelow 
 medium in quality, are fast becoming recognized by a very large 
 portion of the practitioners of dentistry, and believing that their 
 successful utilization depends as much upon a scientific adapta- 
 tion of means, to ends, as does the successful utilization of gold 
 depends upon manipulative ability, I purpose offering some sug- 
 gestions which, while they may not fully educate to the use of 
 " plastics " from the high analytical standpoint that must entirely 
 govern this when based upon fature collegiate instruction, will, 
 nevertheless, give such aid to those who desire to experiment 
 in this direction as will enable them to produce results which 
 will be eminently satisfactory alike to patient and operator, and 
 this, too, in the very cases where even the most skilful manip- 
 ulators in gold fail ignobly. 
 
 To this end I shall first discuss the indications which point 
 to the employment of sluj single plastic material for the making 
 of a filling, and then pass to the consideration of those combi- 
 nations which are the essentials to the perfect development of 
 that system of tooth- salvation which is based upon the electro- 
 chemical theory of Dr. S. B. Palmer, and which attributes the 
 failure in operations mainly to " incompatibihty of filling ma- 
 terial with tooth-bone." 
 
 It is now just twenty-five years since I commenced the 
 work of " Systematic Development of Plastic Filling." It has 
 been, with me, a " labor of love," one in which I engaged under 
 
 19 
 
20 PLASTICS AND PLASTIC FILLING. 
 
 ^lie favorable auspices of hearty encouragement from profes- 
 sional elders for whom I had the highest respect ; whose attain- 
 "^^ ments as practitioners were unquestioned, and whose allegiance 
 
 to dentistry was undoubted. 
 
 It has been a long, and sometimes tedious, path which I have 
 trodden, but the interest has been ever increasing, and the glean- 
 ings from the way-side have proven to me, and to thousands of 
 my fellow-creatures, productive of an ample harvest of mutually 
 satisfactory results. 
 
 During the first six years, progress was naturally slow, but at 
 the expiration of that period I had obtained such data, as that 
 the prosecution of experiments seemed not only warrantable, 
 but to be demanded. 
 
 As I was early educated to the value of " a record " I desired, 
 as a preliminary to long continued, further work, that the con- 
 clusions which had been obtained should be recorded^ that they 
 . could be referred to, be the outcome what it might. 
 
 To this end, I proposed, as the subject for discussion at the 
 meeting of the Pennsylvania Association of Dental Surgeons, 
 held March 12, 1861, " the consideration of the so-called osteo 
 plastic materials for filling teeth." Although the subject was 
 not so stated, the discussion was, under direction, confined to 
 the then new " oxy-chloride of zinc." As / had " proposed " 
 for that meeting, I asked my friend Dr. C. Newlin Pierce to 
 propose "amalgam " as the subject for the next meeting, April, 
 telling him that I desired particularly to obtain a general ex- 
 pression of opinion in regard to that material, and also wished 
 to place myself upon record for an especial purpose. 
 
 Eeference to the discussion of that subject as found in the 
 Cosmos for May, 1861, page 548, will show that I had not only 
 the results of my own " six years " of observation, but the 
 markedly favorable views of the members toward amalgam, to 
 sustain me in a continued series of investigations in connection 
 even with that hitherto questionable compound. 
 
 This was, to me, a matter for congratulation, as I was then 
 about to commence a gradual increase in relative proportion of 
 plastic fillings to those of gold, and it became important that 
 this increase should be definite in materials as well as in degree. 
 I therefore decided upon amalgam, gutta-percha stopping, and 
 
PLASTIC FILLING. 21 
 
 oxy-cUoride of zinc for materials, and upon six per centum of 
 fillings as an amount of annual substitution of plastics for gold 
 wliicli would permit of careful observation and of healthful prog- 
 ress. 
 
 This, of course, could not be done positively, but it was don« 
 so approximately, as that at the close of the ninth year I found 
 myself filling all cavities in teeth helow medium in structure 
 with plastic materials. 
 
 By this time the demands for services had reached a point 
 which permitted of selection of cases upon my part, and I re- 
 solved to confine my work thenceforth, as much as possible, to 
 the saving of soft teeth, a labor which I then recognized would 
 eventuate in the exclusion of gold as a filling material. 
 
 It can readily be imagined that I viewed this result as a matter 
 of serious import, for I felt that its outgrowth must naturally 
 be an uncompromising attack upon the time-honored and fondly 
 cherished articles of belief that " gold is the best material for 
 filling teeth," and that " eminent skill in working gold is the 
 basal requirement for superiority as a dentist ; " but even for 
 this I had been collaterally prepared, largely through the instru- 
 mentality of my cherished friend and able instructor. Prof. 
 Eobert Arthur, 
 
 Note. — It is a source of the greatest comfort to me to have the written proofs 
 of the warm friendship which existed between Prof. Arthur and myself even to 
 the period of his last illness, and to he able to say that he smiled approvingly 
 upon the picture of himself, which he had presented to me, when he saw it in my 
 office as the first in the "Gallery of Dental Heretics." 
 
 I had already enjoyed the opportunity for observing the ex- 
 cellent results of many years of practice based upon his teach- 
 ing in regard to the leaving of decay in cavities, for the protec- 
 tion of the pulp. I had heard the violent denunciation with 
 which this teaching had been assailed, and had seen the cold- 
 ness with which the " eminent " men of 1860 had turned their 
 faces from this " disreputable " practice ; and I had lived to 
 hear this innovation taught, as universally accepted, and to see 
 that the vast majority of the virulent opponents had been forced 
 to practise upon this teaching. 
 
 This naturally gave me faith to believe that other tenets, if 
 
22 PLASTICS AND PLASTIC FILLING. 
 
 luilt upon the sand, would fall, and that other teachings, if 
 founded on a rock, would stand. 
 
 Time and experiment would establish truth, and in no other 
 way could it be established ; therefore, from this period, I de- 
 clined all new patients with teeth above medium in structure, 
 and more closely concentrated my experiments upon such teeth 
 as are, even now, usually condemned to extraction. 
 
 In seven years more I found myself with a practice which 
 was and is, to say the least, peculiar. 
 
 It is peculiar, in that I seldom see a denture which is above 
 average in quality. 
 
 It is peculiar, in that I have many hundreds of patients for 
 whom I have saved, for many years, the remains of dentures 
 which had been almost lost under excellent operators with gold. 
 
 It has been freely suggested to me that it is easy to save teeth 
 when all those predisposed to decay have been extracted ! and 
 that it is easier to save teeth when arches are so broken as to 
 permit a natural separation of the teeth ! and that persons' con- 
 stitutions are apt to change, and thus the teeth are less liable to 
 decay! but it has seemed to me strange that so many patients 
 have come just lohen every tooth which was predisposed to decay 
 had been extracted, and had thus placed under my charge no 
 teeth except such as were not liable to decay ! And again, I have 
 wondered why, when arches were quite sufficiently broken to 
 permit the natural saving separation of the teeth, the loss should 
 be continued until there were not teeth enough left to permit 
 of natural mastication ! and yet again, to me it seemed the most 
 remarkable of all, that every patient's constitution should 
 change immediately upon placing the teeth under the influence 
 of plastic tilling materials ! 
 
 It is peculiar, from the fact that I am able, with such dentures, 
 selected for their frailty, to meet all indications without resort- 
 ing to " artificial work." By this term I mean to refer to the 
 introduction of sets of teeth upon plates, either partial or com- 
 plete, and do not include as " artificial work " the grafting of 
 porcelain crowns, the insertion of plate teeth as faces to " pivot- 
 ings " or the introduction of porcelain as edges, corners, or as 
 " mosaic " fillings ; all this work, I think, is properly taught as 
 "operative," and I would be understood as so regarding it. 
 
PLASTIC FILLING. 23 
 
 During the past eight years, the requirements of all my patients 
 have not reached an average of one piece of artificial work per 
 annum. 
 
 It is peculiar, in that I have no demand for gold as a filling 
 material. When I had reached this point, it was with little or 
 no surprise that I beheld this peculiar result ; the demands for 
 gold had been steadily diminishing for years; as successive 
 exigencies had arisen, each diflS.culty had been satisfactorily sur- 
 mounted, and each surmounting had opened the way for easier 
 conquering of greater difficulties ; in this work the claims of 
 gold became less obtrusive, until they were finally lost sight of 
 completely. 
 
 With teeth which had been filled and refilled with gold un- 
 til the expenditure had been enormous ; until the repetition of 
 infliction had been such that the mere thoughts of dental visits 
 had become intolerable ; until the gradual increase in frequency 
 of extraction had become an accepted institution ; until all hopes 
 of comfort or tooth-salvation had been lost — what was there to 
 offer in continuance of such practice ? 
 
 With those who had honestly and earnestly made diligent 
 inquiry for "the best," — as test after hest had failed to meet 
 their requirements, — and who had availed themselves of ser- 
 vices, the remaining results of which were evidences of mar- 
 vellous skill, patience, and endurance, and with whom all had 
 proven but a mockery, what was there to offer in continuance 
 of such efforts ? 
 
 With those who were thoroughly dissatisfied with what had 
 been done for them, and who had ample and unanswerable 
 reasons for their views of "first-class" dentistry, in what man- 
 ner would any proposition be received other than for something 
 entirely different in dental work from anything which they had 
 previously experienced ? 
 
 Under such circumstances^ what more positively unavoidable 
 than the "abandonment of gold"? And now, as the result 
 of an immense experience reaching through a period of over 
 twenty years, I have arrived at the same conclusion with my 
 friend Prof. H. S. Chase, and most emphatically endorse his 
 enunciation, " In proportion as teeth need saving, gold is the 
 worst material to use." 
 
24 PLASTICS AND PLASTIC FILLING. 
 
 AETICLE 11. 
 AMALGAM. 
 
 " About the year 1826, M. Taveau, of Paris, advocated the use of what he 
 called ' Silver paste,' for permanent fillings. Under this, as it were, shining title, 
 was ushered into the world what was destined to be for years the Hydra of den- 
 tistry." — History of Dental and Oral Science in America, page 61. 
 
 THIS metallic preparation for filling cavities of decay in teeth 
 was first brought to the notice of the dental profession in 
 the United States, about fifty years ago, through the advertise- 
 ments of two Frenchmen by the name of Crawcour. 
 
 It was called by them the " Royal Mineral Succedaneum," — 
 succeddneum^ a replacer or substitute, — a name which is in- 
 dicative oi fraud, and which, consequently, stamps the adven- 
 turers as unworthy of professional respect. 
 
 Had these persons been unsuccessful pecuniarily, it is more 
 than possible no notice would have been taken either of them 
 or their filling material ; but, as it was otherwise, and as they 
 induced a really large number of the "best people" to submit 
 to their operations, a shower of indignant epithets was heaped 
 upon them by the incensed " first-class " practitioners of that 
 day. 
 
 . From the fact that, among other desirable qualities, the then 
 new filling material was "easily manipulated," its possessors 
 were enabled to fill a class of largely decayed teeth, with frail 
 and broken cavity walls, such as had never been attempted by 
 the most skilful operators then in practice. 
 
 This naturally reflected to their discredit and to the en- 
 hancing of the reputation of the Crawcours. It was in vain that 
 asseverations as to the impropriety of retaining such "worth- 
 less" teeth in the mouth were made by those highest in au- 
 thority. The comfort and satisfaction evinced by such as were 
 enjoying the tangible benefits of the "new discovery" far more 
 than counterbalanced the impression made by the scientific 
 theorists. 
 
 This state of affairs, however, was not of long duration. 
 Every occasional swelling of a face — attributable, as we now 
 
AMALGAM. 25 
 
 know, to existing conditions prior to filling, and -whicli an 
 equally tight wStopping of any other material would have 
 equally induced, — was accredited to the " Succedaneum," and 
 from this false basis every sufferer was enlisted as an antago- 
 nist to the " Eoyal" filling material. 
 
 It was soon proven that, instead of the material being a min- 
 eral compound, it was purely metallic, and consisted of silver 
 and copper rendered temporarily plastic by the addition of 
 mercury. 
 
 This knowledge was eagerly spread abroad among the peo- 
 ple; and every case of excessive flow of saliva — now recog- 
 nized as a very frequent concomitant of periodontitis, and par- 
 ticularly of alveolar abscess — was pronounced mercurial ptyal- 
 ism; and direful tales of wholesale loss of teeth and large por- 
 tions of jaw-bone were freely circulated. 
 
 And yet, despite all this, the use of amalgam steadily in- 
 creased. As years rolled by, the number of those practising 
 dentistry, who employed it, was becoming seriously great. 
 Gentlemen who had some claim to proficiency as manipulators 
 and respectability as practitioners were admitting that its use 
 was warrantable in some cases. Doubts were beginning to be 
 expressed as to the truth of the objections which had been 
 urged against it ; and still more decided opinions were held as 
 opposed to the effects — either local or systemic — which had 
 been attributed to it. 
 
 Under these circumstances, it was deemed needful, for the 
 proper maintenance of the dignity and purity of the Profes- 
 sion, that, as there had been organized an American Society 
 of Dental Surgeons, such official action should be taken by 
 that body as would place, beyond discussion, the line of demar- 
 cation between scientific regularity and discreditable irregu- 
 larity. 
 
 As the initiative in this, a committee was appointed in the 
 year 1841 for the purpose of reporting upon all filling materials 
 of which mercury was a component. 
 
 This committee reported that the use of all such materials 
 was injurious both to teeth and mouths, and that there was no 
 tooth which could be serviceable filled that could not be filled 
 with gold. 
 
26 PLASTICS AND PLASTIC FILLING. 
 
 The report of the committee was adopted "by the society 
 unanimoiisly . 
 
 But even this could not stay the onward course of the ob- 
 noxious compound ; for, in the year 1843, it was found neces 
 sary to pronounce the use of amalgam " malpractice.'''' 
 
 This declaration seems to have been the culmination of the 
 solid wave of opposition ; for, at this time, " information and 
 facts " having been gathered and laid before the Medical 
 Society of the County of Onondaga, New York, it was re- 
 ported as their opinion that, although the '■'■ mineral paste" had 
 undoubtedly produced m,ercurial (?) effects both severe and alarm- 
 ing, yet, nevertheless, the proportion of such cases was small 
 when compared with the great number of instances in which 
 it had been employed ; " but that no care in the combination 
 or use of the paste will prevent its occasional bad effects." 
 
 This was not the kind of report, by any means, that the 
 opponents of amalgam desired, as it was calculated to weaken, 
 rather than to strengthen, their cause, and did eventuate in 
 more critical investigation of the subject at the hands of 
 gentlemen who were not blinded by prejudice, but, on the 
 contrary, were actuated by a desire to judge intelligently in 
 regard to the matter. 
 
 Then it was that fillings of the decried material having done 
 ten years of acceptable service in teeth that had been con- 
 demned by eminent practitioners as unworthy the effort to save, 
 were brought under the observation -of those who recognized 
 evidences of its value in these enduring and continuing proofs 
 of its capability. 
 
 Gradually some of the " better men " began to advocate its 
 occasional employment, and so openly was this done, that the 
 leaders of that day — 1845 — felt that the time for the most 
 energetic action had arrived, and, actuated, as we believe, by 
 a conscientious conviction as to the imminent danger which 
 threatened the profession, and through it those who relied 
 upon its members for the saving of their teeth, ^^Besolved, 
 That a committee of investigation be appointed." 
 
 The duty of this committee was that of calling upon each 
 and every member of the aforesaid American Society of Den- 
 tal Surgeons and ascertaining his views in approval or disap- 
 
AMALGAM. 27 
 
 proval of amalgam, and as to whetlier lie used it in his prac- 
 tice. 
 
 Although this resolution was adopted, it was not until it had 
 been most warmly discussed ; and it is worthy of note, as illus- 
 trating the gradual changing of opinions, that Dr. E. Baker and 
 Dr. Solyman Brown, both of whom were members of the com- 
 mittee of 1841, whose report has been referred to, spoke against 
 the resolution. 
 
 The report of this committee was to the effect, that of nearly 
 fifty members visited, less than a dozen ever used amalgam, and 
 only three positively refused to pledge themselves not to do so. 
 It further insisted that any amalgam was dangerous and unfit for 
 use as a filling material, and concluded with this memorable sen- 
 tence : 
 
 " That any memher of this society who shall hereafter refuse to 
 sign a certificate pledging himself not to use any amalgatn. and, 
 moreover, protesting against its use, under any circumstances, in 
 dental practice, shall be expelled from this society^ 
 
 That any such action should have disgraced the records of 
 any scientific body in this country, during this nineteenth cen- 
 tury, is well-nigh incredible ; but that it should have occurred 
 within the ranks of dentistry, and that, too, while it was in the 
 first throes of young life as a distinct profession, when liber- 
 ality, brotherly love, and, above all, the most perfect freedom 
 of scientific thought and investigation should have been ten- 
 derly nurtured, is simply monstrous. 
 
 It is comforting that we are able to relate the burst of con- 
 demnation which greeted this resolution of expulsion; hun- 
 dreds of practitioners, society men, and others, while declaring 
 themselves opposed to the use of amalgam, also declared them- 
 selves as much more opposed to the wretched policy which 
 threatened punishment as the reward for investigation and ex- 
 perimentation. 
 
 At the next meeting of the society in 1847, for using amal- 
 gam and refusing to sign the required pledge, eleven members 
 were expelled. 
 
 The society had now done its " worst," and in so doing, it did 
 its best! Instead of interfering with the use of amalgam, even 
 in the least degree, its action stimulated more practitioners to a 
 
28 PLASTICS AND PLASTIC FILLING. 
 
 critical investigation of the merits and demerits of a material 
 ■whicli had so exercised the minds of the leading men as to have 
 shaken dentistry to its centre. 
 
 The earnest workers wrought on till 1850 ; each year added 
 to the proofs of the value of the condemned material ; wretch- 
 edly compounded ; wretchedly manipulated ; wretchedly abused ; 
 it was yet standing, after a trial of nearly twenty years, in 
 many a tooth which had been filled by the pretentious French- 
 men ! More carefully compounded ; with better manipulation ; 
 and judiciously used instead of badly abused, it had given such 
 convincing evidence of its utility, and had even so long ago 
 lived down so much of false aspersion, as that many of the 
 members of the American Society felt it a duty that the action 
 of 1845 should be revoked, and the error of judgment evinced in 
 the proceeding be fairly acknowledged. 
 
 This feeling gave rise to more discussion, which resulted in 
 the appointment of a committee to take into consideration the 
 propriety of rescinding the former resolutions of " pledge " and 
 " expulsion." 
 
 If the former action of the society was characterized by 
 narrow-minded bigotry, the report of this committee was even 
 worse. It is true, that it recommended that the resolutions 
 which enforced the " subscription to the protest and pledge 
 against the use of amalgam and mineral paste fillings for teeth, 
 be, and the same are, hereby rescinded and repealed ; " but it 
 did so avowedly " upon the belief that the resolutions had accom- 
 plished the object for which they were designed^ and there no 
 longer existed any necessity for their enforcement^ Can this be 
 credited? And yet this is the record of the transaction. 
 
 Again we are comforted in the knowledge that this con- 
 temptible method of treating so important a matter resulted 
 in the immediate resignation of quite a number of the members. 
 
 Again the years rolled on; as truth was mighty and pre- 
 vailed, so the society dwindled year by year, until at last, having 
 lost all its former prestige^ a meeting was held at which the 
 President — Dr. Elisha Townsend — was directed to call a meet- 
 ing for the consideration of " dissolution." At the meeting of 
 1855, a committee upon this subject was appointed. This com- 
 mittee reported against dissolution, was continued, and the 
 
AMALGAM. 29 
 
 meeting adjourned to meet in New York on the first Tuesday 
 of August, 1856. At that meeting — a very small one — the 
 following committee report was adopted : 
 
 " That we deem it expedient to dissolve this association, and 
 that it be and is hereby adjourned sine dieP 
 
 AETICLE III. 
 AMAL GAM.— Continued. 
 
 IT seems to me, that, for the future good of dentistry, two 
 facets are, at this time, worthy of careful, thoughtful consid- 
 eration: — 1st. That amalgam^ which, from its misuse and abuse 
 at the hands of those who attempted to utilize it, had become an 
 object of unmitigated contempt to those who were recognized 
 as representative men, has practically proven itself to possess 
 qualities such as have compelled respectful recognition as a 
 most valuable filling material ; and, 
 
 2d. That such radical change of opinion in regard to amal- 
 gam had been wrought, hy sor)%e means, during the passing of 
 twenty years, as that the official acts which were esteemed need- 
 ful in opposition to its use, so far from accomplishing their pur- 
 pose, were directly instrumental in the final dissolution of the 
 attacking organization. 
 
 These two points alone should furnish sufficient reason, to all 
 who have professional interest in this matter, for the exercise 
 of every effort at obtaining information in relation to it, and for 
 the closest scrutiny of all statements, either favorable or unfa- 
 vorable, regarding this very peculiar combination of metals. 
 
 But it is not alone the two facts of gradually growing recog- 
 nition on the one hand, and final "dissolution" of organized 
 antagonism on the other, that the career of amalgam presents 
 for our reflection, but the equally significant ones that some of 
 its strongest opponents were early found arrayed upon the side 
 of its advocates, and were giving proof of the earnestness of 
 their convictions by its frequent use in practice. Some of the 
 men whose names are found upon the first records of the 
 "amalgam war" as loudly outspoken in condemnation of the 
 
 / 
 
30 PLASTICS AND PLASTIC FILLING. 
 
 material, are tliose who in the later of the " twenty years " are 
 but little less moderate in their views of its " unquestionable 
 value in certain cases." 
 
 But, as though all this was not sufficient for amalgam — as 
 though to show completely, and beyond all cavil, its inherent 
 power for overcoming opposition — we find, " strangest of all," 
 that in the very year — 1855 — when " dissolution " of the oppo- 
 sing organization was proposed, and when it was found that 
 the American Society of Dental Surgeons actually did not pos- 
 sess sufficient strength to die (?), its President, Prof. Elisha 
 Townsend, one of the best gold- workers of his day, gave den- 
 tistry Ms sanction to the first formula for the making of an 
 alloy for amalgam that ever had the least pretension to " re- 
 spectabilityr 
 
 This he did as the result of deliberate conclusions ; as the 
 result of long-continued, careful observations ; as the result of 
 an earnest desire to aid more than he had ever done — and that 
 was very largely — ^in the preservation of teeth. 
 
 This he did because he saw, " daily, the evidence that teeth 
 could be saved with amalgam which he could not save with 
 gold." 
 
 As one of the most competent, the most enthusiastic, and 
 the most conscientious practitioners of his profession, he pos- 
 sessed a breadth of base which permitted, nay, insisted upon, a 
 mental recognition of merit wherever evidence of its existence 
 could be shown. 
 
 As an ardent lover of his calling, he welcomed any aid in 
 the development of its resources in the struggle for relief to 
 suffering, and grandly proved his noble disregard of " self" by 
 accepting that which he felt to be, at least in some degree, 
 worthy, even though it came in the "questionable shape" of 
 old-fashioned^ coin amalgam. 
 
 He recognized its merits, ease of manipulation, capability 
 for accurate adaptation to cavity walls, sufficiently resisting 
 to subserve the purposes of mastication, and proven eminently 
 tooth-preserving. 
 
 He recognized its demerit — its one demerit — discoloration : 
 it turned black ; it discolored the teeth ; it disfigured the 
 mouth. 
 
AMALGAM. 31 
 
 Tlie cry of " mercurial ptyalism " lie had not found to be sus- 
 tained by his observations. He felt that the material had been 
 unjustly dealt with, unjustly maligned, unjustly condemned ; 
 and regarding it as one of the " defiant down-trodden," he re- 
 solved to give it aid and countenance for its merits, and to work, 
 if possible, in the direction of its improvement. 
 
 In young life he had been taught the trade of the jeweller, 
 and with the ideas thus inculcated, he naturally accepted, as an 
 improvement, the " refining " of the metals. 
 
 It was thought that by the 'purifying of the silver, the elim- 
 ination of the copper, — which was then held to be a very 
 objectionable ingredient, — and the addition of a large propor- 
 tion of piLre tin, an alloy could be produced which would be 
 decidedly less objectionable than the silver coin. 
 
 The proportions of this alloy — afterward known as Town- 
 sesnd's — were 
 
 Pure Silver 4 parts. 
 
 Pure Tin 5 parts. 
 
 The metals were thoroughly mixed while molten, and were 
 then cast into matrices so shaped as to form ingots suited 
 either for filing with a coarse file, or for turning into shavings 
 in a lathe : these shavings were then rubbed into a sort of 
 powder. 
 
 To the required quantity of alloy, thus prepared, was added 
 a portion of mercury, and these were mixed in the palm of the 
 hand by kneading with a finger. By this means a metallic 
 mixture of doughy consistence was obtained, which might very 
 appropriately be called a " silver paste." 
 
 This was then further " purified " by a process known as 
 " Washing." For thisj the amalgam mass was placed in a small 
 porcelain mortar and rubbed with a pestle, after having had 
 added to it a little absolute alcohol ; the result of this rubbing 
 was a decided blackening of the alcohol, which was then poured 
 off, and, with the addition of more alcohol, the work of rubbing 
 was repeated ; after two or three such " washings " — as they 
 were styled — much less "blackening" was produced, and it 
 was therefore assumed that this process would prevent, or at 
 least dimiuish, discoloration. The mass was then placed in 
 
32 PLASTICS AND PLASTIC PILLING. 
 
 chamois skin, and tlie surplus mercury having been " squeezed" 
 out by pliers, it was packed, artistically, into cavities of decay. 
 
 As we look at all this, with the aid of such light as has been 
 thrown upon the subject by years of systematic, scientific, 
 metallurgic experimentation, it seems very like many other 
 lines of work prosecuted with the very best intentions, but 
 based entirely upon the crudest and most fallacious assumptions. 
 
 Not one of the various proposed " purifying " processes was 
 possessed of any value ; and, what is indeed most peculiar, not 
 one is other than detrimental/ 
 
 A filling material was made which is not nearly so tooth pre- 
 serving, and which, though it is prevented from discoloring — 
 in limited degree — by the addition of tin, is, by this modifi- 
 cation, caused to " shrink " most notably, and from which is 
 taken, practically, all its "edge-strength." The "washing" 
 process, so far from being advantageous, is proven to be other- 
 wise, and, at the present day, nearly all manufacturers of alloy 
 for amalgam caution against it in italics or capital letters ! 
 
 And yet, the dental profession, in the persons of its repre- 
 sentative men, welcomed with open arms the tinned and 
 " washed ^^ amalgam, as introduced by the President of its 
 American Society of Dental Surgeons, and fairly revelled in 
 the seemingly inexhaustible capabilities of this "purified" 
 sinner ! 
 
 The largest and most inaccessible cavities in the frailest and 
 '•most worthless" of teeth were filled just as the Crawcours 
 had filled them 1 Crowns were built upon the roots of molars 
 and bicuspids, and were viewed with complacent pride, with no 
 thought of disgrace, with no fear of mercurial ptyalism ! 
 
 Some enthusiasts even went so far as to make rows of crowns 
 upon cuspid and incisor roots, and then stepped back to admire. 
 
 This was a change, indeed. It is true, there were some who 
 never joined in this acceptance ; but it is also noteworthy that 
 the later record of such has not placed them in any position 
 which entitles them to rank as equal in professional attainments 
 with most of those who warmly espoused amalgam. 
 
 This state of things continued but for a few years, — some 
 three or four, — for, in this length of time, not only had " un- 
 worthy" men, in numbers, abused the trust ofiered under the 
 
AMALGAM. 83 
 
 mantle of respectability, but much, crevicing between fillings 
 and teeth had taken place from undue shrinkage, and much 
 breaking away of edges, both of fillings and cavity walls, was 
 only too apparent; but, worst of all, the "purification" by fire 
 and hy alcohol had not proven equal to the emergency ; and 
 though the discoloration of fillings and of teeth was not nearly 
 so great as with the coin amalgam, yet it was, nevertheless, far 
 too much for the properly aesthetic ideas of good gold- workers, 
 and thus the tide began- to turn. 
 
 Again, it was now time for much of the pathological se- 
 quellee which naturally pertains to teeth that, having been 
 largely decayed and filled, permit a more or less gradual, and 
 more or less painless devitalization and disintegration of their 
 pulps. And thus it was that with quite an amount of disap- 
 pointment in regard to the frequent occurrence of plug-discol- 
 oration, and with increasingly unsatisfactory statistics in con- 
 nection with subsequent peridental irritation and alveolar 
 abscess, the dental mind became exercised in such degree that 
 some of those who were then recognized as leading men ob- 
 tained from Prof. Townsend the following "recantation," as it 
 was called, which was published in the " Dental News Letter " 
 of April, 1858. 
 
 "For the Dental News Letter. 
 
 "AMALGAM. 
 
 "Messks. Editors. — I promised to- report to jovt any change in my 
 practice in the use of amalgam for filling teeth, founded upon further 
 experience. In all that I have ever said or written upon amalgam, I 
 have been very careful not to advocate its use except in those cases 
 which could not be filled with gold, and where extraction was the only 
 alternative. I find my name has been used as authority for its indis- 
 criminate and unlimited use, which I certainly never intended or sup- 
 posed could happen. 
 
 "I wish now to say to the profession that I have entirely abandoned 
 it, and shall never use it again in my practice. I have come to this 
 resolution for reasons which I will now state. In many of the cases 
 where I most relied upon it, and expected to have the best results, it 
 has entirely failed; as in the buccal cavities in molars, when they ex- 
 tended beneath the free margin of the gum, I found that while in some 
 mouths the material remained white and clean, in others it became 
 very black in a few days, and in almost all cases, upon removing thie 
 filling, the under side was blackened, and the same color given to th© 
 3 
 
34 PLASTICS AND PLASTIC FILLING. 
 
 tooth. Again, in the infirm teeth, for which it seemed the only thing, 
 and for which it was best adapted by its plastic nature, many of them 
 had to be removed, owing to suppuration of the gums, caused by the 
 tight closing of the previous vent for the escape of pus. 
 
 " Therefore I have come to this broad conclusion, that a tooth so in- 
 firm as to need a soft filling would be best removed, for the health of 
 the mouth and the health of the patient; and that my practice hereaf- 
 ter will be to advise their removal, and then leave the responsibility 
 with the patient. Elisha Townsend. 
 
 " No. 1606 Locust Street." 
 
 As it was entirely owing to Prof. Townsend's faitli in tlie 
 tooth-saving quality of amalgam tliat I liad been induced to 
 commence experimenting with it, and as I had gradually come 
 to regard even the discoloration of cpin amalgam as a matter 
 of comparatively little moment in non-conspicuous places, when 
 contrasted with the comfortable and, as it seemed, durable 
 saving of a large class of truly valuable teeth, it was with pe- 
 culiarly painful professional feelings that I viewed this retro- 
 grade step — as I thought it — in that work which I esteemed 
 a progressive movement. 
 
 As it was, the latter part of the "recantation" took from it 
 all its power for controlling me. 
 
 I had just then finished a line of work upon the systematic 
 treatment of such teeth as were specifically classed as appropri- 
 ate for amalgam, with the view to preventing the occurrence 
 of such untoward results, and was then instructing my private 
 pupils in such pathology and therapeutics of alveolar abscess 
 as I have since taught and demonstrated in my lectures and 
 clinics. 
 
 I had also entered upon that protracted individual labor 
 which culminated at the meeting of the American Dental 
 Association of 1875, when I joined my friend. Dr. S. B. Palmer, 
 with the conviction that his theory regarding the need for 
 "compatibility" between filling-material and tooth-bone, as an 
 essential for success in saving teeth, satisfactorily explained the 
 results which my accumulated statistics of twenty years had 
 placed before me. 
 
 I engaged in that work with the full recognition of three 
 basal positions in connection with amalgam : 
 
 First. That one of the very best operators of his time — 
 
AMALGAM. 35 
 
 Prof. Townsend — had conceded tkat amalgam was a material 
 possessing, from some cause, a power for saving teeth, which 
 exceeded that of gold, even when worked with his remarkable 
 manipulative skill. 
 
 Second. That all previous opposition to, and aspersion of, 
 amalgam, had been founded upon complete ignorance of it ; while 
 the evil results which were ascribed to it were certainly attrib- 
 utable to other well-recognized causes ; and. 
 
 Third. That the efforts at correcting its demerit, though 
 well-meant, were misdirected. 
 
 It is at this point that I wish it to be distinctly understood 
 and remembered, that the positively deteriorating effects of the 
 change of formula from silver, copper, and mercury, to tin, 
 silver, and mercury, as accepted and advocated by Prof. Town- 
 send, were not recognized for many years. It was not suspected 
 that the " shrinkage " of the so-called Townsend's amalgam ex- 
 ceeded enormously that of the silver coin amalgam ; indeed, it 
 was believed and taught by Prof. Townsend that amalgam ex- 
 panded during its crystallizing, hardening just as does water 
 while passing from the fluid to the solid condition in freezing. 
 
 It was not recognized that the sustaining " edge-strength " 
 of the old amalgam was seriously impaired by the lavish in- 
 corporation of tin. It was not known that the increased 
 "bulging," due to the less controlled mercurial tendency to as- 
 sume spheroidal shape, was the cause of " crevicing," such as 
 was never seen in connection with the old material. 
 
 It was not known that the " setting " of the new amalgam 
 was even slower than that of the old ; for few, indeed, of these 
 "respectable " experimenters knew anything of the setting of 
 any other compound. 
 
 It was alone recognized that the discoloration, though modi- 
 fied, was not sufficiently so to meet with anything but general 
 disapproval. This was the situation when I commenced amal- 
 gam work in 1855. 
 
 The first positions to establish were those of the truth of the 
 assumption that amalgam possessed a " tooth -saving power " 
 which did not pertain to gold ; that instead of being "dangerous 
 and unfit for use," it was advantageous, and, under certain cir- 
 cumstances, eminently fit for use; and that instead of being 
 
S6 PLASTICS AND PLASTIC FILLING. 
 
 "malpractice" at all times to employ it, it was decidedly 
 " malpractice," at times, not to bestow upon patients the great 
 good of its utilization. 
 
 This could only "be done by first learning its proper mode of 
 manipulation ; then filling a large number of cavities in teeth, 
 where its behavior could be compared with that of gold, and 
 afterward waiting for a sufficient number of years in order to 
 determine this. Accordingly, I resolved to fill some hundreds 
 of cavities with amalgam in teeth such as were usually ex- 
 tracted, or were only filled either by protracted operations with 
 tin-foil, or by equally tedious and vastly more expensive oper- 
 ations with gold. 
 
 As this work progressed, — done, as it naturally would be, 
 with the only amalgam with which I was practically conver- 
 sant, "Townsend's," — the possibilities of the material presented 
 themselves with increasing clearness ; and thus it was that, led 
 on step by step, I gradually treated and filled comfortably a class 
 of teeth which, even to my developing conceptions, was some- 
 thing extraordinary, until, within two years, it seemed to have 
 become the task to question, not the necessity for extraction, 
 but the limit to possibility for salvation. 
 
 I had decided upon Jive years as a reasonable length of 
 time for the determination of the question of " superiority 
 as a tooth-saving material," and so markedly had this been 
 shown at the expiration of that period, that I should certainly 
 have questioned my own ability with gold were it not that in 
 many mouths I had also had the opportunity of contrasting 
 with amalgam work many fillings of gold, of comparatively 
 recent introduction, which were the work of those who were 
 deservedly ranked as " first-class " operators. 
 
 At the close of the Jive years of probation, the time did not 
 seem so long to look back upon as it had seemed to look for- 
 ward to, and so I gave another year. 
 
 At the end of this time, I, too, became convinced that / 
 could " save teeth with amalgam which / could not save with 
 gold," and that therefore it was my duty to myself, and to those 
 who were committed to my charge, to use the means, the value 
 of which I had so thoroughly tested. 
 
AMALGAM. 37 
 
 AETICLE IV. 
 
 AMALGAM.— Continited. 
 
 FEOM 1861 to 1875, a period of fourteen years, my progress 
 in tlie substitution of amalgam for gold liad been very 
 considerable" and bad been attended with, very satisfactory re- 
 sults ; this, however, had been largely due to the " combina- 
 tion" fillings — oxy-chloride of zinc, sub-strata, and linings, 
 which I had used since 1860 ; but it was also due, in part, 
 to my gradual change of formula from that of th-e so-called 
 " Townsend"'s." 
 
 This formula, " Townsend's," had also gradually changed ; but 
 while it had done so by greater addition of tin, and had become 
 6 parts of tin to 4 of silver, the alloy to whicb I had been led 
 was composed of 9 parts of tin to 13 of silver. 
 
 I had noticed the wonderful maintenance of integrity on th.e 
 part of the silver coin amalgam fillings ; and though I then 
 shared the prevailing prejudice against the copper which I 
 knew such amalgam to contain, I was, nevertheless, compelled 
 to admit the loss of edge-strength, the greater crevieing, and 
 the general inferiority of amalgam made from the largely tin 
 alloy. For this reason I commenced the increase of silver, and, 
 notwithstanding the loss in the direction of " maintenance of 
 color," continued its addition until I had reached a decided pre- 
 ponderance of that metal. 
 
 The superficial discoloration bad long since lost mucb of its 
 power to stamp the filling as objectionable, in view of extended 
 and long-continued proofs of capability for tooth salvation ; and 
 even the objection of tooth discoloration had. been thus early 
 largely overcome by " lining."" 
 
 So much work seemed to offer in other lines, and so urgently 
 did it press its claims, that nothing like sufficient attention was 
 bestowed upon alloys for amalgam until the papers upon that 
 subject which were presented at the meeting of the New York 
 Odontological Society, held in December, 1874, came to my 
 notice. These I read with the greatest interest and with the 
 most critical circumspection, and I soon found that I must 
 
S8 PLASTICS ANB PLASTIC FILLING. 
 
 either reconsider the whole of my years of experimentation, or 
 take decided issue with the evident tendency of all manufac- 
 turers of alloys. 
 
 But, again, I felt that I must receive even the statements 
 contained in those papers with doubting hesitation, for, with 
 the exception of the experiments and conclusions of Dr. S. P. 
 Cutler, of Memphis, Tennessee, — with which, in the main, I 
 could agree, — there was a confused mass of assertions, experi- 
 ments, analyses, and deductions, which, while they contained 
 much that seemed reasonable, and stated some facts with which 
 I was conversant, yet also contained so much that was conflict- 
 ing or of doubtful value, or was, in my opinion, absolutely in- 
 correct, that I judged it to be for the most part a questionable 
 contribution to knowledge, 
 
 I found reference made to the practical experiments of 
 Messrs. John and Charles Tomes, 1861 to 1872, which I had 
 regarded as conclusive, and had accepted as such, I found the 
 term " oxidation," as almost invariably applied to the discolor- 
 ation of amalgam fillings, corrected by the acceptance of the 
 lony hefore urged, and much more reasonable, hypothesis of 
 " sulphuretting," I found confusing statements, such as an 
 alloy of " two parts silver, one part tin, and about twenty -five 
 per cent, gold," which would be simply, two silver, one tin, and 
 one gold, I found a long list of elaborate experimentation with 
 filled teeth and amalgam pellets, weighed with marvellous ac- 
 curacy, placed in little bottles containing saliva acidulated with 
 nitric, acetic, citric, or hydrochloric acid, and kept in a water- 
 bath inside of another water-bath, at a uniform temperature — 
 blood-heat — for a period of three months, in order to prove 
 by analysis of the saliva whether or not amalgam fillings would 
 be capable of producing mercurial ptyalism, 
 
 I could not reasonably doubt the certificate of the " Professor 
 of Analytical and Applied Chemistry," that the saliva " contained 
 no mercury in solution ; " but I gravely doubted the value of 
 the test as proving anything whatever in relation to the sys- 
 temic influence of amalgam fillings. 
 
 I found analyses, made " through kindness," which, although 
 so full of such glaring discrepancies as scarcely to deceive 
 one who had closely observed in amalgam work, were yet so 
 
AMALGAM. 39 
 
 speciously presented as to grossly mislead tlie mass of inquirers, 
 and tlius prove anything but a " kindness " to them. 
 
 In these the information was given that " Lawrence's " alloy 
 had in it nearly fifteen per cent, of copper ! and " Townsend's 
 Improved," which sold for $2.00 per ounce, was given as com- 
 posed of materials — silver, tin, and gold — in such quantities 
 as would have cost $1.80 per ounce for these alone ! 
 
 From a personal acquaintance with the dealers in alloys, I 
 thought this could not be true. 
 
 About this time I came into metallurgic association with my 
 friend, Mr. Patterson Du Bois, one of the assistant assayers of 
 the Philadelphia Mint ; he had been for some years a patient 
 of mine, and recognizing the deep interest which I took in 
 dental alloj^s, he offered to make for me a series of analyses. 
 
 I eagerly embraced this opportune aid to investigation, and the 
 work was commenced. So great an interest upon his part was 
 soon engendered, that he asked permission to add the power of 
 another assayer to the task ; thus Mr. Jacob B. Bckfeldt became 
 interested with us, and we prepared for extensive and thorough 
 manipulation. The incentive then, to them, was the probability 
 of eventually arriving at an excellent alloy which they could 
 manufacture. The incentive to me, was the evident possibility 
 of so directing experimentation as to secure, promptly, a good 
 result, based upon some reliable data. 
 
 This I felt would be a boon to my profession, my patients, 
 and myself. 
 
 Our first requirement was the purchasing and analyzing of 
 one or more samples of every alloy of note in the market. It 
 was needful that caution should here be used lest attempts should 
 be made to lead us astray. It was recognized that manufacturers 
 might, very properly, regard it as " business " to prepare for us 
 special samples^ if it was known that we purchased expressly 
 for analysis ; we, therefore, as promptly as possible, and largely 
 through the hands of other parties, obtained the desired samples 
 from various cities and countries ; of the most noted we ob- 
 tained three samples each at various times, ranging from one to 
 three months apart. 
 
 As one after another of these alloys were analyzed, two salient 
 points became apparent ; first^ that the analyses given in the 
 
40 
 
 1>LASTICS AND PLASTIC FILLING, 
 
 paper coiiipiled by Prof. T. B. Hitclicock, and presented by 
 Prof. T. H. Chandler, at the New York " Odontological " meet- 
 ing of December, 1874, were almost entirely unreliable, and emi- 
 nently calculated to mislead inquirers ; and, second, tbat witb but 
 two exceptions, viz., the alloys of Drs. Lawrence and Hardman, 
 all the other alloys in the market were based upon one of two 
 ideas, viz., some regarded the addition of small quantities of 
 gold and platinum as essentially advantageous, and others did 
 not ; but practically all agreed that the proportions of tin and 
 silver should be from fifty-five to sixty -five per cent, of tin, and 
 from thirty-five to forty-five per cent, of silver. 
 
 As examples in proof of these positions I offer the follow- 
 ing half-dozen analyses : 
 
 Analyzed by De. E. S. "Wood, 
 Professor of Chemistry in 
 Harvard Medical and Den- 
 tal Schools. 
 
 " Toivnsend's." 
 
 Silver 40.21 
 
 Tin 47.54 
 
 Copper .... 10.65 
 Gold 1.06 
 
 "Arrington's." 
 
 Silver 40.00 
 
 Tin 60.00 
 
 "Walker's." 
 
 Silver 34.89 
 
 Tin 60.01 
 
 Gold 4.14 
 
 Platinum ... .96 
 
 " Townsend's Improved." 
 
 Silver 39.00 
 
 Tin 55.69 
 
 Gold 5.31 
 
 "Lawrence's." 
 
 Silver 47.87 
 
 Tin 33.68 
 
 Copper .... 14.91 
 
 Gold 3.54 
 
 Analyses by Messrs. Eckfeldt 
 AND Dxj Bois, Metalltjrgio 
 Section of the "New De- 
 partttee Corps." 
 
 " Townsend's." 
 
 Silver 42.00 
 
 Tin 58.00 
 
 Copper, none. 
 Gold, none. 
 
 "Arrington's." 
 
 Silver 42.50 
 
 Tin 57.50 
 
 "Walker's." 
 Silver ..... 30.50 
 
 Tin ..... . 69.00 
 
 Platinum ... .50 
 
 Gold, none. 
 
 " Townsend's Improved." 
 
 Silver 43.00 
 
 Tin 57.00 
 
 Gold, none. 
 
 "Lawrence's. 
 
 Silver 47.50 
 
 Tin 47.50 
 
 Copper .... 5.00 
 Gold, a trace (xl^th gr.) 
 
AMALGAM. 
 
 "Johnson & Lund." 
 
 " Johnson & Lund." 
 
 Silver 38.27 
 
 Silver 38.50 
 
 Tin 59.58 
 
 Tin 59.40 
 
 Platinum ... 1.34 
 
 Platinum ... .40 
 
 Gold 81 
 
 Gold 60 
 
 Cadmium not mentioned. 
 
 Cadmium . . . 1.06 
 
 41 
 
 As I liad experimented in the moutli with nearly every alloy 
 analyzed, and was thus conversant with the working qualities, 
 the defects, and the advantages of each, it required but a few 
 weeks to make the necessary deductions for the initial alloy. 
 Eegarding the average proportions of tin and silver, in nearly 
 all the alloys manufactured, as 60 tin and 40 silver, and inform- 
 ing my co-laborers of the advantages which I had noted in the 
 increase of silver, we, after nine preliminary experiments, in- 
 verted the proportions, and commenced with 60 silver and 40 
 tin ; and it is with much satisfaction that I can say, that five 
 years of experiment and observation, done, as we believe, with 
 unbiased care and accuracy, has only strengthened our convic- 
 tions that these hasal proportions — modified by additions of 
 copper, gold, and zinc ; ■ possibly antimony ; more doubtfully^ 
 platinum ; and most doubtfully^ cadmium — will constitute the 
 best alloys for amalgam fillings which can be made /rom the 
 metals that are now accepted as components for such alloys. 
 
 At this point, I desire to enter a protest against the tendency 
 to mislead, which is found in names and statements pertaining 
 to alloys, as I regard the tacit acceptance of them by dentists 
 as a reproach to dentistry. 
 
 Every " gold and platiua " alloy in the market is, at present, 
 composed of more than fifty per cent, of tin, and more than forty 
 per cent, of silver, while the remaining few per cent. — two to 
 seven, only — are found to be of gold and platinum. Now, as 
 the addition of a small proportion of gold in connection with so 
 large a proportion of tin, even though it be in slight degree ad- 
 vantageous; and as the addition of platinum, either in small 
 or large proportions, is, as yet, not proven to be of any benefit, 
 but must be ranked as of " doubtful " utility, these so-called 
 " gold and platina " alloys cannot be, in much degree, superior 
 to the ordinary alloys of tin and silver. I therefore submit the 
 proposition, that, both in 7iame and inference of great superior- 
 
42 PLASTICS AND PLASTIC FILLING. 
 
 ity, these alloys are deceptive, and their acceptance is deroga- 
 tory to the intelligence of dentistry. 
 
 Many alloys are constantly advertised with the assertions of 
 "no shrinkage" and "no discoloration," when the truth is that 
 fillings made from them both " shrink " and " discolor " most 
 notably ; and those that shrink least, as a rule, with very rare 
 exceptions, discolor most ; while those that discolor least, as a 
 rule, shrink most ! Alloys are constantly appearing which are 
 advertised as " superior,"* as "best," as "made by a new proc- 
 ess," etc., which, upon analysis, are found to be composed of 
 the same ingredients, in the same proportions, as have been 
 almost universally used ; their "plasticity," their " setting," their 
 "edge-strength," their "shrinkage," their "color-tests," are all 
 exactly the same with the other average alloys, and yet each 
 has a long list of "testimonials" as to its superior peculiarities 
 from gentlemen who are regarded as eminent in our profession. 
 
 Note. — During the session of the American Dental Association at Niagara 
 Falls, in 1878 — only two years since — I was told by one of the prominent dele- 
 gates that he preferred decidedly the " Arrington" alloy to that which was sold 
 as " Townsend's ; " and upon asking him "Why?" the reply was, "because it 
 works much more plastic, sets much quicker, makes better edges, keeps its color 
 better, and altogether makes amucA better filling ." I could hardly credit my own 
 hearing! for I knew, from analyses, from working, from careful testing, and from 
 many observations in the mouth, that the two alloys, as compounded and cut, 
 were precisely the same, and that the only difference between them was that of 
 size of grain. 
 
 It is a satisfaction to know that this kind of thing must pass 
 away in due time. Already the advanced collegiate instruction 
 provides students with the needful information, both theoretic 
 and practical, in the direction of testing and analyzing alloys 
 which are offered for sale, and also with instruction in the com- 
 pounding and making of all such alloys and other materials for 
 plastic filling as have been proven, by competent testing, worthy 
 of confidence. 
 
 Already the young men go into the field of practice so much 
 better " armed and equipped," in relation to these matters of 
 vital interest and importance, that they are self-dependent, and 
 can far better instruct than be instructed by those whose expe- 
 rience in plastics has been guided by "judgment" rather than 
 by knowledge. 
 
METALS USED FOR AMALGAM ALLOYS. 43 
 
 AETIOLE V. 
 
 ATTBIBTJTES OF METALS USED FOB AMALGAM 
 ALLOYS. 
 
 TWO or more metals combined by melting form an " alloy." 
 One or more metals held in combination with mercury, 
 hy the mercury, form an " amalgam," 
 
 This is the dental acceptation of tKese terms ; and we there- 
 fore find "alloys," containing mercury in very small proportion, 
 added for the purpose of making them more fusible ; but no 
 mixture of metals is regarded as an " amalgam " unless it has 
 mercury as one of its components in suf&cient quantity to ex- 
 ert a combining influence over the other metals. 
 
 Our present theory regarding the formation of amalgam is, 
 that metals which melt at comparatively high temperatures, 
 being so prepared as to permit of the fusing influence of mer- 
 cury, — a metal which is " molten " even at very low tempera- 
 ture ( — 30°), — are, by admixture with mercury, melted into 
 union with it. — Du Bois. 
 
 The acceptance of this theory not only seems to simplify 
 the otherwise complex and mysterious behavior of this pecu- 
 liar filling-material, but aids much in the accurate construction 
 of various alloys with the view to accomplish specific purposes. 
 
 Thus, the "setting" of the amalgam — as the gradual hard- 
 ening of the mass is technically termed — is recognized as due 
 to the secondary cooling influence upon the mercury from mix- 
 ture of such metals as are not molten at ordinary temperature ; 
 and it is readily appreciated, — at least, in a general way, — that 
 the higher the melting-point of the admixed metal, the quicker 
 will be the " setting." 
 
 I say, " in a general way," for it is practically demonstrated 
 • — by platinum — that, in some way, — from physical charac- 
 teristics, — a metal even of very high melting-point may not 
 produce this result; but this is exceptional. 
 
 . The decided " bulging " — as the spheroiding of the mass is 
 termed — of fillings made of alloys largely composed of tin, 
 may be plausibly attributed to the combined ductility and low 
 melting-point of the admixed metal. Under the strong con. 
 
44 PLASTICS AND PLASTIC FILLING. 
 
 trol of a rapidly and rigidly hardening metal, this spheroiding 
 is found to be limited ; under the feeble control of a metal 
 which cools slowly, and when cold is yielding, the gradual 
 spheroiding continues for many months, and even years, until 
 it eventuates in excessive " bulging." 
 
 The " shrinking " of -the mass is also in general, though not 
 in universal accord with the contraction of the metals com- 
 posing it, as they pass from the fluid to the solid state. Thus, 
 tin, losing its fluidity slowly, permits shrinkage in proportion 
 as it is added in quantity. Gold and copper, which lose fluid- 
 ity quickly, and silver, which expands in cooling, notably 
 lessen shrinkage. Platinum — by far the most obdurate of 
 metals used in dental alloys — seems to exercise such imper- 
 ceptible control over shrinkage as to be unworthy of mention 
 in this connection. 
 
 The " plasticity " of an amalgam, using the term as applied 
 to the length of time during which it may be worked, as "it 
 remains plastic for fifteen or twenty minutes," is almost entirely 
 in consonance with the relative proportion of the easily melted 
 tin ; but here again we find platinum increasing this peculiarity, 
 and even in some alloys maintaining a plastic condition in a 
 most undesirable degree. 
 
 The " edge-strength " of amalgam is singularly influenced by 
 the ratio of edge-strength of its components, as compared with 
 their melting-points ; thus, some metals which have little edge- 
 strength and melt at low temperatures, as tin, require to be 
 mixed in large proportion in an alloy before they will seriously 
 impair the edge-strength of an amalgam ; while some metals 
 which have fair edge-strength and require a high temperature 
 for their melting, as copper, in comparatively small proportion 
 of admixture, will marhedly impair the edge-strength of amal- 
 gam ; metals which have reasonably good edge-strength and 
 melt at high temperatures, as silver, add reasonably to the edge- 
 strength of amalgam as their relative proportion in an alloy is 
 increased reasonably ; other metals of fair edge-strength which 
 melt at high temperature, as gold, add notably to the edge- 
 strength of amalgam, especially that made from largely silver 
 alloys, even though added in but small quantity to the alloy. 
 
 In effect upon edge-strength platinum seems to be entirely 
 
METALS USED FOR AMALGAM ALLOYS. 45 
 
 neutral, whether added in small or large quantity. This was 
 tested in amalgams made from alloys containing platinum in 
 varying quantity, from less than one per cent, to more than five 
 per cent. 
 
 The " hardness " or " density " of amalgam seems to depend 
 entirely upon the toughness of the metals composing the alloy. 
 This is a point which would require a vast amount of experi- 
 mentation to establish ; an amount which, at present, would be 
 non-compensating, for the reason that we have no difficulty in 
 making amalgam of sufficient density. Indeed, if we could im- 
 prove in the direction of " maintenance of color " without in- 
 crease of "shrinkage," and without loss of "edge-strength," 
 but by diminishing in " density," it would be rather beneficial 
 than detrimental, for even the least desirable of all the alloys, 
 Townsend's, "Walker's, Arrington's, etc., are more than suffi- 
 ciently " dense " to subserve all practical purposes. 
 
 Note. — The terms " hard " and " dense," though not synonymous in metal- 
 lurgy, seem to have become such in the technical phraseology of amalgam alloy 
 work ; they are used as opposite to " soft," while the term " brittle " is employed 
 as indicative of another characteristic which may pertain either to soft or hard 
 amalgam, it meaning easy to he broken or crushed. 
 
 The metals which are at present used in alloys for dental 
 amalgams, are, silver, tin, copper, gold, zinc, antimony, cadmium, 
 and platinum. 
 
 Note. — Palladium, tellurium, etc., are not included in this list, because the 
 several reasons, that the very high price of the metals — from thirty-five to fifty 
 dollars per ounce — the great difficulty of obtaining them in adequate quantity 
 and the decidedly theoretic value yet pertaining to them as components of amal- 
 gam alloys, were deemed sufficient to deprive work upon them of all practical 
 value, at least so far as pertains to present demands. 
 
 Silver. Argentum. Symbol, Ag. Fuses at 1873° F. Ex- 
 pands on cooling. 
 
 As in 1826, under the auspices of M. Taveau, the name of 
 " silver paste " was given to the prototype of that filling ma- 
 terial now known as " amalgam," so might it reasonably be 
 given to all the amalgams of the present day. 
 
 Silver is the first, the most important, the essential metal of 
 a good amalgam alloy for filling teeth ; it is the largest compo- 
 
46 PLASTICS AND PLASTIC FILLIIirG. 
 
 nent of every truly good " submarine," " usual," or " contour " 
 alloy in the market ; and it will be found by all actual tests, 
 that just in proportion as an alloy contains silver in small 
 amount^ so will it make an amalgam which will not compare 
 favorably^ in its meeting of almost every dental requirement, 
 with those made from alloys which are largely composed of this 
 metal. 
 
 The most ordinary amalgams of to-day, taking that made 
 from " Townsend's " alloy, 60 tin, 40 silver, as the type, are 
 mixed into pastes, with about two-fifths their weight, con- 
 sisting of mercury, a little less than two-fifths tin, and a little 
 more than one-fifth silver, 38 parts mercury, 39 parts tin, 23 
 parts silver = 100 parts ; and yet the silver is the essential, for 
 without it the amalgam would be worthless for filling teeth. In 
 the next grade of alloys are those composed of the same relative 
 proportions of tin and silver, but with the additions of gold or 
 gold and platinum. 
 
 In these the silver is still the essential ; but in the endeavor 
 to keep its proportion small, and to overcome, by the addition 
 of the other metals, the loss of edge-strength and the tendency 
 to shrink and bulge incident to large admixture of tin, it is 
 found that something is yet required to meet the emergency ; 
 and it is therefore proposed, by the manufacturers of such alloys, 
 that they be mixed with the smallest possible amount of mer- 
 cury, be worked in the form of a "kind of powder," and be 
 made into amalgam by packing into the cavity with warm in- 
 struments. 
 
 With the next grade of alloys the stereotyped prbportions of 
 tin and silver are inverted, of these the " old reliable " alloys 
 of Hardman of Muscatine, Iowa, and Lawrence of Lowell, 
 Mass., are the types ; but in these we find the valuable admix- 
 ture of copper in addition to the increased proportion of silver. 
 
 Any operator who has, for many years, wrought faithfully 
 with these alloys, has found no need for " dry powder " in place 
 of well constituted plastic " amalgam," nor has he had to heat 
 his instruments in order to introduce his fillings ; and I am sure 
 that each can poiut to many a monument of "capability for 
 tooth salvation," even in desperate cases, which is alike a marvel 
 to himself and to his patients ; and these results, both that of 
 
METALS USED FOR AMALGAM ALLOYS. 47 
 
 possibility of easy working, and that of eminence in tootli- 
 saving, are d\ie, almost exclusively, to the large proportion, 
 relatively, of silver. 
 
 Again, with progressing gradation, we reach the present high- 
 est type of "usual" alloys, composed of silver, tin, gold, and 
 copper, and represented by the very properly named "Stand- 
 ard" alloy of Eckfeldt and Du Bois. 
 
 Note. — Having been reliably informed that it has been reported, with invid- 
 ious comments, that I have a pecuniary interest in the sale of " Standard " alloy, 
 I would say that, while I cannot see the impropriety of holding such interest^ 
 if I held it, the statement is entirely untrue ; and that I have never had any 
 other business relations with Messrs. Eckfeldt and Du Bois than those of a purely 
 experimental character. 
 
 So far from deriving any pecuniary benefit from the sale of this alloy, I ex- 
 pended my third, of nearly seven hundred dollars, in the work of developing the 
 basal deductions whicli eventuated in the material that has been offered, with its 
 gradual mutations, year by year, to the profession, and of which it is truthfully 
 said that, "acting as a pioneer, the 'Standard' has literally established a stand- 
 ard; " and I also wish to say, that I would willingly have contributed hundreds 
 of dollars more, had it been needed, for the satisfaction which I have enjoyed in 
 the possession of that solid substratum of information in regard to dental amal- 
 gam alloys which I feel has been of so much value to me and mine, and which I 
 think I could not have as well obtained from any other source. 
 
 In these we find the relative importance of the silver even 
 more fully recognized ; and while we cannot regard them as 
 superior to, if even equal with, the three metal alloys, when 
 viewed merely as tooth preservers, we yet cannot deny to them 
 the possession of sharper and stronger edges ; greater rapidity 
 of setting; finer plasticity in working; and a better general 
 maintenance of color. 
 
 To the silver^ then, we ascribe the position of metal of first 
 importance ; it is essential to the proper setting of the amalgam ; 
 it notably maintains the bulk integrity of the filling, and it 
 forms, with the sulphuretted hydrogen, which is more or less 
 constantly brought into contact with it in the mouth, sulphide 
 of silver, which, though it discolors the filling and also the 
 tooth, is nevertheless highly conducive to the permanent saving 
 of teeth which are not only largely decayed, but markedly pre- 
 disposed to continued decay. 
 
 Tin. Stannum. Symbol, Sn. Fuses at 442° F. 
 
48 PLASTICS AND PLASTIC FILLING. 
 
 I have placed this metal second on the list, because, although 
 it is a component of comparatively modern introduction, and 
 is largely ante-dated by copper, and although its introduction 
 well-nigh ruined a material which had bravely withstood the 
 assaults of unscrupulous prejudice for more than a quarter of a 
 century, it has at length, by long and elaborate experiments, 
 been assigned a position in which, under control, it becomes 
 the second in importance upon the grounds of quantity and 
 usefulness. 
 
 All such alloys as I should favorably regard, have from 35 
 to 48 per cent, of tin ; it is found that by the addition of copper 
 and gold, both antagonists of " shrinkage," the most deleteri- 
 ous of the effects of tin can be counterbalanced; that under this 
 control sufhcient silver can be used to obviate a detrimental 
 loss of edge-strength; that the retardation of'" setting" is pre- 
 vented, and that the tin not only loses its power for harm, but 
 becomes an ingredient of manifold utility ; it greatly augments 
 the facility of amalgamation ; it aids in producing a good color 
 and in preventing discoloration; and it diminishes conduc- 
 tivity. 
 
 Copper. Cuprum. Symbol, Cu. Fuses at 1996° F. 
 
 The "Koyal Mineral Succedaneum" was an amalgam of 
 mercury, silver, and copper ; it was made frorti silver-coin filings 
 which were composed of an approximate to nine-tenths silver 
 and one-tenth copper ; the amalgam was made by mixing about 
 equal parts of mercury and filings; the result was a mixture 
 consisting of 50 parts mercury, 45 parts silver, 5 parts copper 
 = 100 parts. 
 
 This material saved teeth even though abused and misused, 
 but its surface discolored outrageously, — it darkened teeth 
 abominably, — and the soluble salts of the uncontrolled copper 
 in fillings entering pulp cavities and canals, so permeated the 
 dentine and ccmentum, coloring them a livid green, as to give 
 rise to a warrantable suspicion that to the presence of this 
 metal might be attributed the subsequent death and exfoliation 
 of such teeth. 
 
 Note. — As I cannot but admire the ingenious reasoning of Mr. Tomes in re- 
 gard to this form of discoloration, I quote from him : 
 
 " The sulphide of copper, under the influence of exposure to air and moisture, 
 
METALS USED FOR AMALGAM ALLOYS. 49 
 
 readily becomes oxidized, and forms the sulphate. Hence it is almost certain we 
 shall have sulphate of copper formed upon the exposed surface of the filling. Now 
 this sulphate is freely soluble, and hence is likely to permeate the dentine, when it 
 will again be converted into sulphide, whilst the sulphides of other metals, not 
 being so readily converted into soluble salts, will not so thoroughly permeate the 
 teeth." 
 
 For this reason copper was early looked upon as a very 
 objectionable ingredient of amalgam, and "virgin silver" wa& 
 the first desideratum ; but I have constantly noticed, during all 
 the many years in which my professional brethren in our own 
 country have been reaping the harvest of a fearfal loss of soft 
 teeth, under the regime of elegant gold-work, and have been 
 vainly endeavoring to stay the tide of destruction by an in- 
 crease of the already lavish incorporation of tin in amalgam, 
 that my professional brethren in other countries, particularly 
 England, have been saving just such teeth by using amalgam, 
 of which copper was a component ; and that in some of these 
 filling materials this metal abounded in marvellous quantity ; 
 thus it was that, as I was continually lessening the tin, and in- 
 creasing the silver, in my efforts to save the teeth which had 
 become wrecks from being repeatedly filled with gold, I began 
 thinking favorably of the despised and discarded copper. 
 
 I was not alone in this, for others seemed so evidently im- 
 pressed with the value of the diminishing — silver — and aban- 
 doned — copper — metals, that the heavily silvered three-metal 
 alloys were produced. It is one of the peculiarities of the 
 "judgment" practice, that hundreds of practitioners have, for 
 a long time, used Lawrence's and Hardman's alloys with most 
 satisfactory results to themselves and to their patients, who 
 would have been horror-stricken if their " knowledge " had told 
 them that each contained copper ! 
 
 Note. — It is but little more than one year since a paper upon the subject of 
 "amalgams " was read by a Professor of Dental Metallurgy, from which I quote : 
 " Most dentists would hesitate about employing an amalgam known to contain 
 copper; yet I was much surprised recently (!) at the result of a careful analysis 
 of an amalgam filling which had done good service for twenty-three years, dur- 
 ing which period it had retained a perfectly bright and smooth surface exteriorly. 
 . . I found its composition — after freeing from mercury — to be tin, 55 parts* 
 silver, 40 parts ; copper, 5 parts." 
 
 From an educational point of view, it seems sad that, at this late day, a teacher 
 of dental metallurgy should have been thus "surprised." 
 4 
 
50 PLASTICS AND PLASTIC FILLINGS. 
 
 But it is not alone tlie marked compatibility of these par- 
 tially copper amalgams with tooth-bone which characterizes 
 them as peculiar ; for it has also been noted, and commented 
 on, that pulps seem to evince decided toleration for them. It 
 has been my own experience in practice, that teeth, in which 
 " deep " and " very deep " cavities of decay had been filled with 
 amalgams containing copper, have, as a rule, behaved better 
 than those which had been filled with amalgams which did not 
 contain this metal. My record of pulp-saving — noted in each 
 case after five years of trial — is very significant in its connec- 
 tion with the presence of a portion of copper ; for, while I do 
 not presume to say that it is, as yet, proven beyond question 
 that pulps do maintain their vitality better under amalgam 
 fillings which contain copper than under those which do not, 
 I must nevertheless admit that observation has seemed to point 
 so conclusively in this direction, that I should, in my practice, 
 permit, with the exception of tin, no metal filling which did 
 not contain copper to approach a pulp. 
 
 And yet another direction in which copper seems useful as 
 an adjunct, is its singular properties as alloyed with tin — the 
 alloys of tin and copper — " hard brass ; " " bronze" may prop- 
 erly be regarded as among the most curious of metallic mix- 
 tures. From these soft and yielding metals are compounded 
 some of the best alloys for brass ordnance ; the unyielding 
 "anti-frictions," and, even more peculiar still, the obdurate 
 "speculum metal." 
 
 ' Very lohite alloys result from admixture of copper with tin, 
 and this effect is noted in amalgam ; by proper manipulation — 
 which will be given in place — the face of such an amalgam 
 filling can be finished with exceeding whiteness ; and although I 
 cannot but think that in certain mouths the presence of the 
 copper tends much toward increasing discoloration, yet, the 
 usual result^ particularly under the controlling influence of an 
 addition of gold, is the making of very light-colored fillings, 
 which retain their color remarkably well. 
 
 To copper, then, is ascribed the power of diminishing, in a 
 manner. " shrinkage," as copper amalgam neither expands nor 
 contracts ; it favors rapidity of "setting;" it is accredited with 
 power to add to the "compatibility" of the filling material 
 
METALS USED FOE AMALGAM ALLOYS. 51 
 
 with, tooth-bone, and thus better saves the teeth ; it is thought 
 to produce greater harmony between filling material and dental 
 pulp, and thus promotes " toleration " of foreign material, in 
 close proximity, on the part of that organ ; it adds to the im- 
 mediate whiteness of the amalgam, while its tendency to gradual 
 discoloration is notably under control ; for these reasons I re- 
 gard it as a most valuable component of dental amalgams. 
 
 Gold. Aurum. Symbol, Au. Fuses at 2016° F. 
 
 This metal is one of those more recently added to the list as 
 an ingredient of dental amalgam alloys ; it has been but very 
 few years — eight or ten — since systematic experiments with 
 it were inaugurated ; opinions are yet varied in regard to some 
 of its effects upon amalgam, but enough are in unison to show 
 that it is worthy of place in our considerations, while the con- 
 cluding work of the " New Departure Corps " left it with me, 
 so far as its possibilities are concerned, in the position of the 
 most undetermined element. 
 
 In relation to its effect upon " shrinkage," there can be but 
 one opinion ; the " specific gravity " work of Dr. C. S. Tomes 
 established not only the fact of its prevention of shrinkage, but 
 the ratio of its preventive power ; but opinions concerning its 
 control of color, and particularly its control of " setting " and 
 " density," are antagonistic in the extreme. 
 
 In the paper of Prof. Hitchcock (Harvard Dental Depart- 
 ment), it is stated that an English alloy of gold one part^ tin two 
 parts, silver three parts, is said to keep its color well, but does " not 
 become very hardy And again, he says, " Gold does not harden 
 well with mercury. When added to an amalgam of silver and 
 tin, however, it produces a decided effect in lessening not only 
 the shrinkage, but also the tendency to ball up and round itself 
 in the angles ; but while it does this, it greatly retards the set- 
 ting ^ 
 
 The Professor of Dental Metallurgy, of University of Penn- 
 sylvania Dental Department, states that he found an alloy of 
 gold one part^ silver four parts, tin five parts, — as simplified 
 from his " two thousand five hundred milligramme " arrange- 
 ment, — when mixed with half its weight of mercury " retained 
 its sharpness of edge, hardened well in a few minutes^ and ap- 
 parently filled all the requirements of a dental amalgam." 
 
52 PLASTICS AND PLASTIC FILLING. 
 
 At first sight the discrepancy of these statements is confusing, 
 but a closer examination renders them even more so. Eeduc- 
 ing the " parts " of the two alloys to the usual analytical " hun- 
 dredths," for the purpose of easy comparison, we find them to 
 be, practically, 
 
 which " does not become very hard" and in which gold 
 greatly retards the setting," 
 
 Gold . 
 
 . 17 ~ 
 
 Tin . 
 
 . 33 
 
 Silver . 
 
 . _50 
 
 -./I 
 
 100 
 
 Gold . 
 
 . 10" 
 
 Silver . 
 
 . 40 
 
 Tin . 
 
 . 50 
 
 
 100 
 
 which " hardens well in a few minutes,' 
 
 From an immense experience in the making, testing, and 
 working of amalgam alloys, I should infer that the state- 
 ment of Prof. Hitchcock was largely based — as he intimates 
 
 — upon hearsay; while the other statement is evidently based 
 upon actual experiment ; and yet the two statements are emi- 
 nently calculated to mislead, and especially when contrasted 
 as we have them above ; for it would naturally be inferred that 
 the second formula, in regard to which it is said that, when 
 properly mixed, it " apparently filled all the requirements of a 
 dental amalgam," must be decidedly the better of the two ; 
 while the facts are that, when properly mixed, the supposed 
 " English amalgam " is much superior to the other. It " sets " 
 just as quickly; gives as good a "color-test," — maintenance 
 of color in dilute sulphuretted hydrogen water; — hardens 
 with greater density; permits of finer cutting, and "works" 
 with greater smoothness ; has less " shrinkage " and better 
 " edge-strength," and yet it does not " fill all the requirements 
 of a dental amalgam." 
 
 Note. — I think Prof. Hitchcock must have been entirely misinformed re- 
 garding the alloy to which he has referred ; for I do not know of any such ma- 
 terial, and I do not think it likely that anything so peculiar — if in the market 
 
 — could have escaped my notice. The " first cost " of such an alloy would be at 
 least four dollars per ounce in the ingot. The addition of the manufacturers' 
 and dealers' profits almost always makes the retail price treble, and sometimes 
 more than quadruple, the amount of " first cost ; " and such an alloy would not, 
 
METALS USED FOR AMALGAM ALLOYS. 53 
 
 therefore, be sold for less than ten dollars per ounce. So far as I know, there is 
 none such advertised. 
 
 From our line of experiments it lias been concluded tliat 
 gold, more than any other metal, in proportion to the small 
 amount required, diminishes " shrinkage," increases rapidity of 
 "setting," imparts /i7ie grained plasticity, controls "mainte- 
 nance of color," and secures desirable edge-strength to amal- 
 gams ; and furthermore, that, like any " balancing power," its 
 great usefulness is developed in exact ratio with the accurate 
 meeting of requirements on the part of the other component 
 metals. 
 
 It is for this reason that I have given it as an "undetermined 
 element." I am of the opinion that the best proportionate 
 quantity of gold will eventually be proven to be from five to 
 seven per cent., while the value of this definite proportion will 
 depend entirely upon the accurate proportionment of every 
 other component. It will require many years to arrive at any 
 positive conclusion on this point ; but upon it, as it seems to 
 me, depends in considerable degree the ultimate production of 
 an aesthetic " usual " amalgam for filling teeth. 
 
 Antimony. Stibium. Symbol, Sb. Fuses at 840° F. 
 
 This metal has been, and is even yet, used in a few of the 
 many alloys at present offered to the profession with the ster- 
 eotyped assertions as to their " superior excellence." The only 
 difference between them and the general alloy consists in the 
 addition of a portion — sometimes quite large — of antimony. 
 It is conceded that the one property of " shrinkage " is con- 
 trolled by this modification, and that the grain of plasticity is 
 finer ; but our experiments resulted only in duplicating pur- 
 chased alloys which, when made into amalgams, proved so ex- 
 cessively dirty in mixing and in working, that, for this reason 
 alone, all further efforts with .this metal were abandoned. 
 
 Shrinkage is so satisfactorily under control, and fine-grained 
 plasticity is so easily obtained, that, as the working of the best 
 amalgams is yet accompanied with undesirable degree of "soil" 
 to the hands, any ingredient which only accomplished the two 
 requirements above mentioned, and did it with excessive in- 
 crease in so objectionable a direction, seemed to us unworthy 
 of much consideration. 
 
54 PLASTICS AND PLASTIC FILLING. 
 
 Zinc. Zincum. Symbol, Zn. Fuses at 773° F. 
 
 As the alloys of copper and tin have been spoken of as very 
 curions and valuable, so may the alloys of zinc and copper be 
 spoken of as eminently " ancient and honorable ;" and when 
 to these must be added the quality of exceeding usefulness, we 
 may well come to the consideration of zinc with befitting care 
 and deference. Not that it has been, as yet, proven to be of 
 such lasting value in dental amalgam alloy as to reflect credit 
 upon its " made record ;" but that, like gold, its possibilities 
 may be something of vast importance. 
 
 Added to the usual " 40 silver, 60 tin " alloys, in the propor- 
 tion of from 1 to 1| parts in 100, it seems to control " shrink- 
 age " perfectly. So decided is this, that fillings made of such 
 amalgam, in tubes of five or six times the diameter of those 
 usually employed in the "leakage test" — with blue or purple 
 ink — give no perceptible indications of permeation of fluid. 
 
 Added to such alloys as Lawrence's, Hardman's, Pierce's, 
 — made from analysis of " Standard," — " Standard," etc., in the 
 proportion of even less than 1 part in 100, the same result is 
 produced. Besides this, it seems to impart an additionally 
 "buttery" plasticity to the amalgam, which gives it excep- 
 tionally fine working quality, and also to add to the already sat- 
 isfactory whiteness of the filling, and to its maintenance of color. 
 
 Altogether, the effects which seem to be due to limited ad- 
 mixture of zinc are expressed to each other, by experimenters, 
 in using the somewhat vague but comprehensive word, '■^pe- 
 culiars It is hard to say just what this means, or in what de- 
 gree in any direction, but it signifies that the " feel " of the 
 " make " is different ; that the " amalgamating " is different ; 
 that the " working " is -different ; that it " sets " differently, and 
 that the final result is different ; and that it is satisfactorily so. 
 This line of work is of such comparatively recent date — a few 
 years — as yet to be entirely within the boundaries of "ex- 
 perimental." It seems to promise well, but the intiraate relations^ 
 as well as the distinct differences^ which exist between zinc and 
 cadmium should be remembered. 
 
 Cadmium. Cadmium. Symbol, Cd. Fuses at 442° F. 
 
 It is about thirty years since cadmium amalgam alloy was 
 suggested to the profession by Dr. Thos. "W. Evans, of Paris. 
 
METALS USED FOR AMALGAM ALLOYS. 55 
 
 The promises of tliis alloy were certaiiilj very alluring It 
 was easily amalgamated ; the amalgam was readily inserted ; it 
 did not discolor ; it " set " with surprising celerity ; it made a 
 sufficiently resisting filling. What wonder, then, that the gentle- 
 man who introduced it was pleased with the material ? His 
 mention of it, however, was very soon proven to be not in ac- 
 cordance with the slowly, and sometimes painfully contracted 
 habits of deliberation, watchfulness, and long-enduring patience 
 which pertain — as a part of himself — to the old experimenter, 
 but must be viewed as entitled to our respect and gratitude 
 from the generosity of his outpouring of that which seemed to 
 him so very valuable an adjunct to the practice of his profes- 
 sional brethren. 
 
 My own experiments with cadmium amalgam were disastrous 
 in the extreme. Presuming upon the high authority of its 
 recommendation, I received it with the cordiality of a young 
 enthusiast, introduced a large number of fillings, — nearly two 
 hundred, — and was delighted with it. 
 
 My satisfaction was, however, very short-lived, for only three 
 or four months passed before sundry indications presented, 
 which aroused my suspicions as to the uniform integrity and 
 durability of the material, — these were an occasional, but evi- 
 dent crevicing at edges ; a gradual softening and disintegration 
 of some fillings ; and the yellowish discoloration sometimes 
 apparent in adjoining tooth-structure. 
 
 Having kept my usual list for statistics, under the head of 
 " cadmium work," I immediately sent for several patients to 
 examine as to how things were progressing. Strangely enough, 
 so large a proportion of the fillings looked well and seemed to 
 be doing good service, that my suspicions were quieted until 
 the time arrived for the periodic dental examinations which I 
 early instituted, and endeavored by persuasion and by argument 
 to enforce, among my patients. 
 
 Then it was that I became fully impressed with the utter 
 worthlessness of the specious amalgam. Quite a number of fill- 
 ings were found completely "demoralized," and, what was far 
 worse, quantities of dentine had become thoroughly decalcified 
 and stained to a bright orange-yellow color — sulphide of cad- 
 mium. 
 
66 PLASTICS AND PLASTIC FILLING. 
 
 I at once undertook tlie most thorongli examination possible, 
 and commenced the work of reparation of damages. So far as 
 the removal of fillings in pulpless teeth^ and their replacement 
 by those of less pretending, but more trustworthy materials 
 was concerned, all was well enough ; for, in that work, no 
 other suffered nearly so much as I. But of the teeth containing 
 vital pulps, of which I am truly thankfal there were compara- 
 tively few, the most became " devitalized." There was but a 
 very occasional recollection of pain, and this had been of so slight 
 a degree, as not to have compelled a visit for relief upon the 
 part of any one ; but in such cases, as I gradually removed the 
 yellovv' portions of tooth -bone until I finally entered the pulp 
 cavities, I found more or less thoroughly devitalized pulps. In 
 some instances, where thick septa of dentine existed between 
 the bottoms of the cavities of decay and the pulp cavities, the 
 pulps were still living ; in these I carefully excavated until I 
 had removed all yellow tissue, saturated the remaining dentine 
 with creosote, as was then the practice, and refilled. 
 
 Some, even of these pulps, have since died under the later 
 fillings ; the putrescent pulps have given rise to peridental irri- 
 tation, and the fillings have either been removed or the teeth 
 have been tapped and treated. Others, again, have lived and 
 are yet living ; but even these, as I occasionally see them, act as 
 reminders of my woful experience with cadmium amalgam. 
 
 But cadmium is yet a component of a few of the present 
 amalgam alloys. It is introduced in some alloys, in very small 
 proportions, from one to three per cent., by those whose expe- 
 rience seems to dictate to them the propriety and the advantage 
 of so doing. It is an open question as to the advisability of 
 even this slight admixture, but for such alloys as have this 
 metal incorporated in large proportions, and even such exist, 
 unblushingly advertised upon the pages of our dental publica- 
 tions, I have but one opinion, and that is, that they should be 
 denounced with the utmost severity. 
 
 As I have said, the question of the absolute expunging of 
 cadmium from the list of metals permissible in amalgam al- 
 loys, or of its retention as one which, in very limited quantity, 
 may be possessed of real value, is yet an open one. So far as 
 I hnoWj there are no positive grounds for its retention ; there 
 
METALS USED FOR AMALGAM ALLOYS. 57 
 
 are no reasonable deductions wliicli point to it as of any value. 
 I do not know of any essentials to a good alloy, whicli are posi- 
 tively given by cadmium, unless in detrimental quantities, tbat 
 are not attainable by means wbicb are not' questionable ; and as 
 I cannot but fully appreciate the probable impossibility, on my 
 part, of any further extended experimentation, such as I have 
 prosecuted and enjoyed during the past twenty-five years, I 
 desire to caution the workers of the present day as to the need 
 for care in their endeavors for the "positive placing" of cad- 
 mium. 
 
 While I could not do other than concur with the advisabil- 
 ity of careful^ thoughtful^ observant^ and, above all, patient cad- 
 mium experiments, I nevertheless feel that I should be dere- 
 lict if I did not give it as an opinion, that, though cadmium is 
 a most enticing metal, it is also a most dangerous one. 
 
 Those forewarned, surely should be forearmed. 
 
 Platinum. Platinum. Symbol, Pt. Fuses, alone, only be- 
 fore the oxy-hydrogen blowpipe, or in a very powerful blast 
 furnace. 
 
 Although this metal, has been so generally thought to be an 
 important one in amalgam alloys, and although its value has 
 been so positively stated and so tacitly acknowledged as to 
 have made its nam,e alone, without any known quantities, or 
 even actual presence^ of sufficient power to bestow position of 
 eminence upon material to which it is given, I have nevertheless 
 placed it last upon the list from the fact. that, /or years^ it has 
 passed from the notice of our " New Departure Corps," and has 
 been, by us, just as thoroughly ignored as it has been, in pub- 
 lic, ostentatiously paraded. 
 
 In the proceedings of the " New York Odontological," Dec, 
 1874, page 52, in Dr. E. A. Bogues' paper on " The physical 
 properties, etc., of dental amalgams," the following is given : 
 
 "Fletcher's Platinum and Gold alloy, marked YIII., and 
 yielding upon assay these two different results : 
 
 Gold . . 3.60 Gold . . 5.10 
 
 Platinum . . 3.30 Silver . . 39.50 
 
 Silver .. . 37.63 ^"^ Tin . . . 55.40 
 
 Tin . . , 55.47 Platinum, none." 
 
 The information that a ^^ platinum and gold alloy " had as 
 
58 PLASTICS AND PLASTIC FILLING. 
 
 one of its components "platinum none^'' is certainly amusing; 
 but tliat " dentistry " should have accepted and used such ma- 
 terial because it was '■'■platinum and gold alloy," is assuredly 
 discreditable in the extreme. 
 
 And yet in this instance ignorance was bliss, and perhaps it 
 is true that " when ignorance is bliss, 't is folly to be wise ! " for, 
 of the two alloys analyzed, that with the " platinum none " is 
 the better alloy ! Its 39.50 of silver and its 5.10 of gold gives 
 it quicker setting, better edge-strength, better color, and less 
 shrinkage than pertains to its rival with only 37.63 silver and 
 3.60 gold ; while in each the more than 55 of tin does all 
 it can in the way of decreasing " setting," permitting " bulg- 
 ing," and consequent "crevicing" and diminishing "edge- 
 strength ; " surely these things are difficult to regulate, even 
 with "judgment." 
 
 The conflicting opinions regarding platinum are quite equal 
 in antagonism to those which have been quoted concerning 
 gold. 
 
 In "New York Odontological," Dec, 1874, page 20, Dr. Cutler 
 says : " Filings of platinum and mercury rubbed together . . . 
 do not amalgamate readily. . . . There appears to be no affin- 
 ity between the two." "I combined platinum with silver and 
 tin in small proportion, and found that just in proportion to the 
 amount of platinum was the amalgamation retarded." " The 
 next experiment was with platinum and gold, one equivalent 
 of platinum and two of gold; . . . after the lapse of two 
 weeks it was not firm^ ... in fact, it did not harden to any 
 extent." The next experiment was with one part platinum, 
 two parts gold, and three parts ordinary alloy. " The mass was 
 grayish-white, rather dirty in appearance, and did not become 
 hard and jirmP The next experiment was with one part of 
 platinum, one part of gold, two parts of silver, and two parts 
 of tin. After twenty-four hours the lump was " white and pure, 
 but not hard e7iouyh for durable work ; " "in twenty-four hours 
 longer — in forty-eight hours — the mass had become quite as 
 firm as ordinary amalgam." This was a mixture of platinum, 
 gold, silver, and tin — the combination which has been stated as 
 alone utilizing platinum. 
 
 These experiments were not alone made with " alloys," but 
 
METALS USED FOR AMALGAM ALLOYS. 59 
 
 were a "line of work " in wTiat we call " meclianical mixes " — 
 done evidently with, the idea that such mixing was equivalent 
 to alloying. This is by no means the case, but the work is 
 interesting as showing the effect of platinum when thus 
 " mixed," 
 
 Mr. Fletcher says — so states Prof, Hitchcock — that "the 
 amalgam called platinum- amalgam is composed of the ordi- 
 nary silver and tin alloy with, ten per cent, fine gold, to which, 
 sufficient platinum is added to cause it to set quicklyP 
 
 The quantity required to produce this effect is not given ; but 
 it may be well to recall the fact that without the platinum the 
 formula is practically the sam^e as quoted from the University 
 of Pennsylvania Professor of Metallurgy, which, minus plati- 
 num,^ he said, " hardened well in a few minutes." 
 
 Prof. Hitchcock evidently accepted the theory of the quick- 
 setting control of platinum, for he says of palladium, " Wlren 
 added to a gold, silver, and tin amalgam, it hastens the setting 
 about the same as platinum does." 
 
 "When we read from Dr. Cutler that the " mechanical mix " 
 of " filings and mercury do not amalgamate readily ; " " do not 
 form a metallic mass at all, but remain in the form of a dark 
 powder ; " and that " there appears to be no affinity between 
 the two," and when we read from the University Metallurgist 
 that " a very smooth and plastic amalgam may, however, be 
 formed by rubbing some finely divided platinum, such as is ob- 
 tained by precipitation, with mercury, in a heated mortar ; " 
 but that " an amalgam composed of platinum and mercury does 
 not harden well," and that in an alloy of tin, silver, and plat- 
 inum the properties were " greatly impaired by the addition 
 of platinum ; " and that in an alloy of tin and platinum " the 
 property of setting was almost entirely lost," and when all ex- 
 perimenters agree that palladium amalgam " sets " with such 
 rapidity that unless it is made very soft it cannot be properly 
 inserted as a filling, it seems doubtful as to its hastening setting 
 " about the same as platinum," 
 
 But, again, while it has been usually accepted that, in some 
 way, platinum is a very advantageous adjunct in an amalgam, 
 and while to it has been ascribed the power of preventing dis- 
 coloration alike of fillings and of teeth ; the increasing of plas- 
 
60 PLASTICS AND PLASTIC FILLING. 
 
 ticity ; the promotion of setting, and the production of a gen- 
 erally excellent ( ! ) filling material, it has been taught by a few 
 that "the real value of platinum" pertains only to its combi- 
 nation with tin, silver, and gold. 
 
 Its " real value " in this connection is stated to be the giving 
 to such alloys the properties of "almost instantly setting" and 
 of "greater hardness." 
 
 Even granting this to be true, the "real value" of this metal 
 seems to be of very little, if indeed it is of any, moment ; for 
 if, as we know, alloys can be made without it, composed only 
 of silver, tin, and gold which will " set " with even more than 
 desirable rapidity, and if, as I have stated, the softest of all the 
 amalgams are needlessly hard, and the harder ones would be 
 very much improved if they could, without loss of other valu- 
 able qualit}^, be made softer, then the "real value" of platinum 
 becomes so questionable as to render it more than probable that 
 it may he positively detrimental. 
 
 But the line of work done by our "corps" does not corrob- 
 orate either assertion concerning much control of discoloration ; 
 much control of "plasticity;" much control of "setting," or 
 much induction of " hardness ; " and for amalgam, so far as 
 "general excellence" — vague and unscientific as is the term — 
 is concerned, I believe that one part of zinc is worth a dozen 
 times more than a dozen parts, or any other number of parts, 
 of platinum. 
 
 So far as is proven, the value of platinum seems to be just 
 equal with that of tin. Every alloy which we made or experi- 
 mented with, that had, in place of certain proportions of plat- 
 inum, the saine equivalents of tin, set the same ; shrank the 
 same ; gave the same color-test ; had the same edge-strengtli ; 
 and, with the exception of being, perhaps, a little less plastic 
 and a little less tough, worked the same; and, so far as could be 
 positively demonstrated, were practically the same. 
 
 My conclusion is, therefore, that except in name (!)the metal 
 platinum, is valueless as a component of amalgam alloys for fill- 
 ing teeth. 
 
THE- MAKING- OF AMALGAM ALLOYS. 61 
 
 AETIOLE YI. 
 THE MAKING OF AMALGAM ALLOYS. 
 
 THE making of alloys for amalgam is a brancli of dental 
 manufacture the importance of whicli is but little realized. 
 I took occasion to direct attention to the large proportions 
 which this had assumed, when I read my paper upon " Plastic 
 Filling as a Power in Dentistry " at the American Dental As- 
 sociation, August, 1878, 
 
 • 
 
 Note. — This paper may be found in the "Dental Cosmos" for September, 1878, 
 
 page 474. It was not published in the " Transactions " of the Association. The 
 
 reason for non-publication is given in the following letter from the chairman of 
 
 the Publication Committee. 
 
 174 State Street, Chicago, April 5, 1879. 
 Dr. J. Foster Flagg, Philadelphia. 
 
 Dear Sir. — In explanation of the fact that the paper read by you at the last 
 meeting of the American Dental Association does not appear in the " Transac- 
 tions," I am instructed by the Publication Committee to say that it was after 
 careful consideration that they unanimously decided not to publish it. 
 
 In the Constitution are the following instructions to the Publication Commit- 
 tee : " They shall superintend the publication and distribution of such portion 
 of the Transactions as the Association may direct, or the Committee judge to be 
 of sufficient value." The Committee felt compelled, under the latter clause of 
 these instructions, to exclude this paper, it being mainly a statement of the claim 
 of the writer, of his greater success in saving teeth — by means of a system of 
 practice not described — over that of other practitioners. 
 
 The decision of the Committee was not actuated by any personal prejudice, nor 
 influenced by any opposition to the doctrine advanced in this paper, but was 
 governed solely by a sense of duty. 
 
 Believe me to be, in behalf of the Publication Committee, 
 
 Very truly yours. 
 
 I there showed that, although amalgam was rather decried 
 as a filling material; that it was only used in exceptional cases; 
 that its employment was usually spoken of as derogatory to 
 "first-class" ability, and that the almost universal testimony 
 of speakers upon it was, that they filled with it but " very in- 
 frequently," it nevertheless required the united manufacturing 
 capability of more than twenty makers of alloys to supply the 
 constantly increasing demand. 
 
 Nearly every manufacturer of " dental supplies " has, through 
 " a long and elaborate series of experiments," arrived at the 
 
62 PLASTICS AND PLASTIC FILLING. 
 
 same formula, and eacli is " superior " to all the others ! By 
 most dealers the " alloy" is advertised as an " amalgam," and it 
 is thus designated by those who purchase and use it ; the dis- 
 tinctive difference between the two being, by custom, ignored. 
 
 Occasionally, some speaker has given his formula and " method 
 of making," and in the aggregate these are singularly har- 
 monious ; from first to last the silver is melted first, and the tin 
 is then added in pieces, or each is molten separately, and the 
 two melts are poured together. 
 
 As platinum and gold became adopted as ingredients, the 
 process continued essentially the same. Among the most recent 
 of these " methods " is that given by the Professor of Operative 
 Dentistry, University of Pennsylvania, — "Pennsylvania Odonto- 
 logical," March, 1879, — in which, after stating that "much de- 
 pends upon the proper alloying of the metals," it is still directed 
 that " the silver should be melted first, and when at a boiling 
 heat the platinum should be added in very small particles, either 
 rolled into thin ribbons or cut into minute pieces. Next, the 
 gold should be added ; and, lastly, the tin,^'' — the italics are 
 mine. 
 
 Even with this periodic dissemination of instruction, the 
 making of alloy seems to have been undertaken but by few 
 practitioners ; no education in regard to it has been given in 
 most of the colleges, and not one graduate in an hundred has 
 any definite idea, either of the components, the proportions, or 
 the properties, of the materials he purchases for the filling of 
 teeth, other than as given him upon the printed envelope or 
 the paper of " directions." And all this, notwithstanding the 
 time-honored " annual announcements " from " chairs of Dental 
 Metallurgy." 
 
 Such " methods " are not held in high esteem by the " New 
 Departure " metal-workers, for their method is so very different. 
 
 For the making of alloy, the hessian, or sand crucible, is 
 used. In this is first fused a very liberal portion of borax, 
 sufficient in amount to fill the crucible at least one-third full of 
 the molten salt. This is intended for a " flux." Any ordinary 
 coke or coal-fire is all that is required for the " melt ; " but it 
 is, of course, more systematically, and perhaps more readily, 
 done at the usual dental or smelting forge-fire. 
 
THi; MAKING OF AMALGAM ALLOYS. 63 
 
 Having perfectly fused the borax, in it the tin is melted 
 Jirstj requiring but a low temperature, and, after it is melted, 
 the granulated silver is added.* It is really remarkable, when 
 the high fusing-point of silver is considered, with what facility 
 this metal is taken up by the molten tin. These two metals 
 are thoroughly stirred together with an iron rod, or clay pipe- 
 stem of small size, and suitable length, and when completely 
 incorporated, the copper — small pieces of wire — is added. This, 
 like the silver, notwithstanding its fusing-point of almost 2000°, 
 is soon melted, and may be equally homogeneously mixed. 
 Lastly, the gold is added, melted, and all is thoroughl}^ stirred 
 together with the iron rod or pipe-stem. 
 
 When perfectly melted and mixed, the fused mass should be 
 quickly poured into a broad, open, flat, shallow matrix made 
 of iron or soap-stone ; this favors prompt cooling, and thus 
 secures the greatest uniformity of distribution to the com- 
 ponents, 
 
 I cannot understand how any reasonable method of working 
 metals, even silver and tin, could result in such wholesale 
 separation of the components of an alloy as that described by 
 the Professor of Metallurgy at the April, 1880, meeting of the 
 New York Odontological. I can believe that there might be 
 approximation to the almost complete separation of the silver 
 from the tin, thus leaving one end of the ingot nearly all silver, 
 and the other nearly all tin, by very slow cooling and very 
 careful work /or the defiyiite accoraplishme^it of that purpose; but 
 I cannot think that any one, in the least degree proficient in 
 " making melts," need ever fear such untoward experience. 
 
 On the contrary, I know that novices in the working of 
 metals, " first course " men, are in the habit of making good 
 samples of three and four metal alloys with but comparatively 
 little practice. 
 
 The " cutting " of the alloy into " grains," " filings," or " a 
 kind of powder," as it is variously given by the manufacturers, 
 is a matter of grave consideration to them, as it is a trouble- 
 some and expensive process, just in proportion to the goodness 
 of the alloy. Thus, a heavily tin, two metal alloy, can be cast 
 into cylindrical ingots, and " rasped " up into " grains," or better 
 yet " turned " up into " shavings," with rapidity and cheapness; 
 * See Appendix, Section 9. 
 
64 PLASTICS AND PLASTIC FILLING. 
 
 wliile with a fine, "heavily silvered, four metal alloy, the work 
 is very different, and is both laborious and much more ex- 
 pensive ; but for individual need it is only necessary that the 
 file be used. 
 
 Here again the quality of an alloy is quite accurately tested ; 
 for while the coarse files known as " vulcanite files " are best 
 for cutting all " low grade " or " ordinary " alloys, they are not 
 nearly as good as finer files for cutting "high grade " alloys. 
 
 It is one of the " tests " for a good alloy, that it shall not, 
 in cutting, " clog " a fine file. 
 
 After the alloy is "filed up," the filings should be passed 
 through a fine wire sieve ; this removes all coarse pieces, bits 
 of leather from the wire file-brush, and other undesirable im- 
 purities which may become mixed with them during the filing. 
 After this the filings should have a magnet passed through them 
 until no iron filings adhere to it ; they should then be spread 
 out over a broad surface, and carefully blown, either by the 
 breath or small bellows, to remove any dust ; this should be 
 done gently^ as the finest of the filings are light, and easily 
 blown away, while they are the best of all the cut alloy. 
 
 The filings are now prepared for use, but they are, most de- 
 cidedly, not ready for use. 
 
 Although manufacturers have not hesitated to cut up large 
 quantities of alloy, and keep it " in stock," without fear of de- 
 terioration, it has nevertheless been thought by them, and by 
 the profession generally, that such keeping was detrimental, 
 and from this belief some practitioners have filed up or turned 
 up but small portions of their ingots at a time, in order that 
 their material might always be " fresh," as it has been termed. 
 Among all the many errors which have obtained in connection 
 with alloys and with amalgam, there is probably no other more 
 decided tban this. There is no alloy made that does not work 
 better and make better results after it has been cut for several 
 weeks than can possibly be the case where it is "fresh," and in 
 this particular, as in every other, the distinctions are so marked 
 between " ordinary" and " high-grade " alloys, that an " expert " 
 can decide in a few minutes, simply by mixing, not only the 
 quality of any given sample of alloy, but, approximately, hoiv 
 long it has been cut. 
 
THE MAKING OF AMAT.GAM ALLOYS. 65 
 
 An alloy must he poor that will mix witli a small, relative 
 proportion of mercury and work satisfactorily wlien freshly 
 cut. And inversely I can state that no reall}^ good alloy, such an 
 one as will, when properly " aged," rank well as amalgam under 
 the "setting," "shrinkage," "edge-strength," and "color" tests, 
 is fit to work unless it has been cut at least two months. In 
 my own practice, I never use any alloy that has not been cut 
 for three or four months, and I prefer them even very much 
 older than that; alloys that are "dull of response," that is, 
 which apparently work well amalgamated when freshly cut, 
 shrink notably, set slowly, bulge markedly, and have little or 
 no edge -strength. 
 
 During a line of work upon the mixing of various fresh-cut 
 alloys, it was found that, by placing them in a revolving glass 
 cylinder, and maintaining revolution for several hours, two 
 simultaneous effects were produced. Not only were the alloys 
 thoroughly mixed, but a result analogous to that which is given 
 by " time," became apparent. The working quality was much 
 improved, and for this reason the double name of " mixer " and 
 "ager" was given to the instrument which is here illustrated.* 
 
 Qualitative Testing of Amalgam, Alloys. — The following 
 brief directions, for which I am indebted to Messrs. Eckfeldt 
 and Du Bois, may be found useful and interesting to those who 
 desire a general idea of the method of making some simple 
 qualitative tests of amalgam alloys. 
 
 Dissolve from ten to twenty grains of the alloy in a small 
 quantity of nitric acid, say half an ounce, by the application of 
 gentle heat. 
 
 The appearance of the solution gives the first clue to its com- 
 position ; the tin, being undissolved, shows itself in the form 
 of a white precipitate. 
 
 Should gold be present, the tin will be colored from a light 
 to a deep purple according to the proportions ; suflEice it to say 
 that less than one-half of one per cent, will make quite a de- 
 cided purple. 
 
 The presence of platinum, with or without the gold, gives the 
 tin a dirty, blackish color, and the platinum being partly dis- 
 solved by the nitric acid, the whole solution is, likewise, dis- 
 colored. 
 
 5 * See Appendix, Sec. 1. 
 
6Q PLASTICS AND PLASTIC FILLING. 
 
 Copper, in quantity, colors the solution green or blue. 
 
 These are the first general appearances which determine the 
 presence of tin, gold, platinum, and, possibly, copper. 
 
 For the determination of the remaining metals found in these 
 alloys, the solution should first be evaporated to dryness ; then 
 dilute with distilled water and eliminate the oxide of tin by 
 filtering. 
 
 The silver will be precipitated as a chloride, flocculent, but 
 densely white, by treating filtrate with very dilate hydro- 
 chloric acid. Eliminate by collecting on filter. 
 
 Copper will show itself by a blue color, if a small portion 
 of the filtrate be now tested by pouring into it a little ammonia. 
 Should this not appear, treat the filtrate with sulphuretted hy- 
 drogen. If cadmium be present, it will be shown by a bright 
 yellow precipitate. If the color be not bright yellow, but 
 brownish, it indicates that some silver has either been left un- 
 precipitated by the chlorine or has passed through the filter. 
 
 Should the ammonia test decide the presence of copper, treat 
 filtrate with sulphuretted hydrogen as before directed, and a 
 black precipitate of sulphide of copper will result, unless modi- 
 fied in color by a large percentage of cadmium. Collect this 
 copper, or mixed precipitate, on a filter (preserving the filtrate) ; 
 if copper and cadmium both be present, the precipitate must be 
 boiled in dilute sulphuric acid ; this dissolves the cadmium and 
 leaves the copper to be collected on a filter. 
 
 Treat this last filtrate with sulphuretted hydrogen, adding a 
 few drops of ammonia to the solution, to modify hyper-acidity. 
 The bright yellow precipitate will be the sulphide of cadmium. 
 
 Lastly, boil down the first filtrate from copper, or mixed pre- 
 cipitate referred to above, until nearly dry, to expel the sul- 
 phuretted hydrogen ; then add a little pure water and a solution 
 •of carbonate of soda until neutralized. The presence of zinc 
 is then proved by the white carbonate of zinc now precipitated. 
 
TESTS FOR AMALGAM. 67 
 
 AETICLE TIL ' 
 TESTS FOB AMALGAM. 
 
 THE various "tests" for amalgam ar-e (1) the "quality" test; 
 (2) the " shrinkage " test ; (3) the " setting " test ; (4) the 
 "color" test; (5) the "edge-strength" test; (6) the "tooth-con- 
 serving" test. 
 
 First. Quality Test. — The quality of an amalgam depends 
 upon the quality of the alloy with v/hich it is made, the quan- 
 tity of mercury with which it is mixed, and the method by^ 
 which the filings are incorporated with the mercury. The 
 quality of the mercury has no appreciable influence upon amal- 
 gam ; it is only needed that it be pure, that is, practically free 
 from metallic admixtures ; thus, the mercury as sold in the ten- 
 pound stone bottles is perfectly adapted for making dental 
 amalgam, and the necessity for having it " double distilled " — 
 a quality thought to be something finer than is usually sold — ■ 
 is merely ideal, / " double distill " by pouring from my ten- 
 pound bottle of "battery mercury " into my box- wood mercury 
 holder.* 
 
 Mercury which has been used for making a button of amal- 
 gam, and has been " squeezed out " as superfluous, should not 
 be returned to the mercury holder, as it contains an indefinite 
 amount of various metals in unknown quantities. The presence 
 of these metals, held loosely for a length of time in the mer- 
 cury, not only prevents the making of a " known " amalgam by 
 its use, but likewise so affects the mercury as to render it a less 
 powerful melter of the other metals, thereby requiring a larger 
 relative proportion of mercury than is desirable in the making 
 of any given amalgam. 
 
 Testing quality is, however, governed by different considera- 
 tions from making amalgam, though the need for pure com- 
 mercial-mercury is equal in both directions. And thus it 
 is, that while each kind of alloy requires a definite relative 
 amount of mercury and especial methods of mixing for the 
 attainment of the best filling possible to be made from it, all 
 alloys require that the same relative proportion of mercury 
 * See Appendix, Sec. 2. 
 
68 PLASTICS AND PLASTIC FILLUfTG. 
 
 shall be used in tlie making of " test-buttons" tbat shall decide 
 " quality." 
 
 The reason for this is, that it is essential that one definite 
 jproportion of metal he known ; and, as the mercury is the only 
 metal to be added, of this must be made the definite addition. 
 
 For this purpose, then, equal parts of mercury and alloy 
 should be taken, — these proportions have been chosen for the 
 reasons that they are most easily weighed, — the mercury being 
 placed "in one scale and the filings in the other, and these ac- 
 curately balanced; and that no alloy in present general use 
 requires such an amount of mercury for the making of an 
 amalgam fit for filling purposes. 
 
 Filling purposes and testing purposes are different ; in that 
 for filling, rapidity of accomplishment of purpose — within the 
 bounds of obtainance of excellent result — is desirable ; while 
 for testing, reasonably slow progress better demonstrates rela- 
 tivity of consecutive showings. 
 
 Having weighed the portions of mercury and alloy to be 
 tested, the method of mixing is practically immaterial. The 
 mix may be made in the palm of the hand ; it may be a 
 "shaken-mix," — as suggested by Mr. Fletcher,^ — pressed into 
 form by his mould ; or it may be the usual " mortar-mix," 
 with the subsequent palm-kneading. In no case, however, 
 should any of the mercury be removed from the mass. Thus, 
 if the mass be pressed in a Fletcher mould, it should be al- 
 lowed to retake the mercury squeezed out in the packing. 
 
 By any of these various methods of mixing, "buttons" of 
 different degrees of plasticity are made which are in known 
 accord with the varying composition of alloys. 
 
 Buttons made from alloys of tin and silver — largely tin — 
 are very soft, having the peculiar plasticity of tin; these "set" 
 slowly ; gain edge-strength with the utmost deliberation ; never 
 attain an acceptable edge-strength ; retain for a long time — an 
 hour or more, according to the relative quantity of tin — a de- 
 gree of exterior softness which permits of marking by rubbing 
 gently with the finger, and are easily crushed or broken after 
 several hours of hardening. 
 
 Those made from alloys of silver and tin — largely silver — 
 are much firmer in consistency ;. have the peculiar crepitation, 
 
TESTS FOR AMALGAM. 69 
 
 indicative of silver, in making; "set" mucb. less deliberately; 
 gain edge-strength, more satisfactorily ; attain fair edge-strengtli 
 in from two to four hours ; and lose in an hour that exterior 
 softness which permits of " finger-marking." 
 
 Those from alloys of tin, silver, and copper — largely tin — 
 have the peculiar " feel " given to alloy by copper. This may 
 well be called peculiar^ and yet, to one who is a decided ^' ex- 
 pert " in this method of analyzing, it is very cognizable. 
 
 Note. — Some years since, Dr. Weston — of Weston's alloy — was calling upon 
 me in relation to these, to us, very interesting matters, when a sample of alloy, 
 which I had requested a friend to obtain, was handed to me. I opened the 
 packa.ge, and giving Dr. Weston some of the alloy, requested an " approximate 
 analysis." Flubbing it up with the palm-mix and gently manipulating it for a 
 few minutes, he remarked, " It's a little peculiar. I think it is pretty nearly 
 equal parts of tin and silver, with -er a little -er copper in it — say about four or 
 five parts in a hundred." It was Lawrence's alloy. 
 
 Test amalgams of these alloys "set" less slowly than those 
 of tin and silver of this grade ; but the " setting " due to cop- 
 per is "grainy," not firm, and is accompanied with a character- 
 istic whitening of the mass. They remain softish for quite a 
 time, — nearly an hour, — and their edge-strength is not good. 
 According to our experiments, these legi7i to represent " good 
 alloys." 
 
 Alloys of silver, tin, and copper — largely silver — are in- 
 creasedly satisfactory in all directions: they set with increased 
 promptness ; they harden satisfactorily and with firmness ; they 
 have reasonable whiteness ; they have desirable edge-strength ; 
 in an hoar they have all these test requisites in test sufficiency. 
 
 Alloys of tin, silver, and gold — largely tin — are those which, 
 first give apparently " excellent " testings : they work with a 
 pleasant plasticity; they harden reasonably well and with 
 reasonable firmness ; their edge-strength seems to reach " quite 
 satisfactory" in quality; if they are cut with fineness, in the 
 form of thin, light, shavings, bulky in mass but diminishing 
 most notably on amalgamating, the mass sets more promptly, 
 and all these qualities are particularly noticeable to those who, 
 as a rule, have been habitually working the tin and silver — 
 largely tin — alloys. 
 
 It is due to these facts that testimonials, honest in their inno- 
 
70 PLASTICS AND PLASTIC FILLIN-Q. 
 
 cence, are found attaclied in great numbers to tlie advertise- 
 ments of this tin^ silver, and gold class of alloys. The givers 
 have used alloys " comparatively infrequently ; " they have used 
 them upon the recommendation of their makers, and with no 
 knowledge of components or proportions. They have learned 
 to recognize certain peculiarities of make, set, hardness, and 
 capability of finish, as characteristic of " amalgam," and the 
 marked differences, which even a little gold is able to confer 
 upon even the stereotyped alloys, appear to them as " something 
 extraordinary!' ' 
 
 When such alloys are subjected to " general testing," their 
 deficiencies become very decided, and they are proven, in real- 
 ity, to be but little better than their tin and silver predecessors 
 of the amalgam " middle age." 
 
 Buttons made from alloys of silver, tin, and gold — largely 
 silver, but sufficiently of gold — are the beginning of something 
 fine. They mix with combined rigidity and plasticity ; their 
 crepitation is that due to the combination of silver and gold, 
 " short, sharp, and decisive," and peculiarly pleasing to the initi- 
 ated ; their setting is prompt, firm, and dense ; they evince 
 excellent edge-strength ; and at a time when the buttons of 
 amalgam from tin and silver can readily be scraped away with 
 the finger-nail, the buttons of silver^ tin, and gold can be as 
 readily handsomely burnished. 
 
 I have had the pleasure, frequently, of demonstrating these 
 things, and from expressions of developing convictions, great 
 satisfaction, and marked degree of interest, I have been led 
 to conclude that, if this line of work is done by one familiar 
 with It, no other is capable of so thoroughly impressing the 
 student with the wonderful difference between alloys, the 
 absolute need for " knowledge " in this connection, and the 
 perfect facility with which, hy its possession^ one can separate 
 the "tares" from the "wheat." 
 
 In the quality testing of alloys of silver, tin, gold, and cop- 
 per, or of those of tin, silver, gold, and zinc, the work is much 
 increased in difficulty and delicacy. To do this with any ap- 
 proximate to accuracy^ it is necessary that one shall have made 
 hundreds of makes of known different alloys ; and even then it 
 can only be " inferential." But with this experience, a general 
 
TESTS FOR AMALGAM. 71 
 
 idea can be formed upon which can be predicated, more surely, 
 the fine work of analyzing such materials, and the finer work, 
 still, of suggesting such modifications as would probably be im- 
 proving. 
 
 Here is a field, indeed, for the thought, energy, and discus- 
 sions of the "coming dentist," — afield which, though it has 
 yielded fine results, has been but comparatively superficially 
 cultivated. While I think that the workers of " The ISTew De- 
 parture Corps " have done dentistry solid service in the labors 
 which they have accomplished, I yet feel that each member of 
 that band now, more fally than ever before, recognizes that, in 
 the aggregate, the task performed is, to the task yet to be done, 
 as but a little part. 
 
 In testing the quality of such alloys as contain cadmium, the 
 presence of this metal is usually indicated very promptly upon 
 amalgamation ; in proportion of three or four per cent, the 
 " cadmium feel " — a sort of slippery stick or greasy catch — is 
 just sufficiently apparent to excite suspicion; it is also dirty 
 in its working, and leaves much soil closely adherent to the 
 fingers ; it also causes '■' cadmium setting " in sufficient degree 
 to be noticeable. This setting is rapid but devoid of strength. 
 Antimony gives some of these peculiarities, but cadmium is 
 detected with reasonable facility after it has been experienced 
 a few times in testings. 
 
 Zinc, as a component of amalgam, is not brought into special 
 notice by the " quality test," except as it seems to cause adhe- 
 sion of the mass to the pestle during making; this is so marked 
 in alloys containing zinc in from two to four_per cent, that it is 
 well worthy of note. 
 
 Second. Shrinkage Test. — I believe that to Mr. John Tomes 
 first occurred the idea of testing the bulk integrity of amal- 
 gam ; his work upon this point was done about twenty years 
 ago. So firmly had the belief in "expansion" of amalgam 
 become impressed upon the dental mind, that, notwithstanding 
 the conclusive proof given by Mr. Tomes in favor of " contrac- 
 tion " or " shrinkage," as it is variously designated, as shown 
 by the whole line of tin and silver amalgams, dentistry con- 
 tinued to believe, as it had been taught before, that amalgam 
 expanded in its setting. 
 
72 PLASTICS AND PLASTIC FILLING. 
 
 Mr. Fletclier, of Warrington, England, followed in this line 
 of experiment witli Ms practical "tube tests." Of these I 
 have done an immense number. The advantage of the " tube 
 test " over that of the " amalgam micrometer " is the possibility 
 of doing a number of experiments in a limited time, as tube 
 after tube can be packed and set aside for results, while with 
 the micrometer each packing has to remain in the instrument 
 until the result is obtained. This requires from several days 
 to many months for each experiment ; but while the tube test 
 is practical, reliable micrometric work is more accurate, and 
 particularly as regards relativity of contraction or expansion, 
 and is therefore essential to progressive experimentation. 
 
 Note. — I must agree with the experience given by Dr. Geo. B. Snow, " Odon- 
 tological Proceedings," Dec, 1874, page 67, in that I have never been able to 
 obtain the peculiar mirror-like appearance which I have seen in some specimen 
 tubes sent to this country by Mr. Fletcher, even though I have repeatedly tube- 
 packed amalgam made from his alloys mixed both dry — powdery — and with 
 sufficient mercury for plastic working. 
 
 For the introduction of the " index " amalgam micrometer, I 
 believe we are indebted to Prof. Hitchcock ; but the work done 
 by him with his instrument, as presented at the New York 
 meeting, while so very questionable, upon the slightest exami- 
 nation, as to make it seem incredible that it should have been 
 presented in good faith by any one to any scientific body, is, at 
 the same time, in a certain sense, instructive, and may, by 
 giving it only a passing notice, prove of value as a warning 
 to other dental organizations, before which such papers might 
 be read in future. 
 
 The whole series of experiments are so loosely done ; so 
 completely inharmonious in their relation the one to the 
 other ; so impossible of production, if done with an instrument 
 of the least pretensions to accuracy, in the hands of an experi- 
 menter of even limited experience, that no value whatever, as 
 bases for amalgam alloy work, can attach to them. 
 
 I have already stated that the analyses are unreliable so far 
 as regards practicality, and have shown that the marketed alloys 
 of the same names are not composed of the metals or propor- 
 tions there given — with one exception ; but I shall have to 
 now suppose that the analyses were correctly made frona 
 
TESTS FOR AMALGAM. 7B 
 
 samples furnished by the various manufacturers — a thing 
 which I am sorry to have to do — in order to prove the want 
 of accord between the results as " shrinkage measurements^ 
 
 Alloys made of the metals given, in the proportions given, 
 do not relatively ^^ shrink^''^ as stated, whether mixed "dry," 
 "medium," or "full;" whether "washed" or "not washed." 
 Two or three examples will show this : 
 
 "Arrington's " Silver . . 40 Expanding component. 
 Tin ... 60 Contracting component. 
 "Shrank .0045." 
 
 " Townsend's Improved." 
 Silver . . . 39.00 Expanding component. 
 Gold .... 5.31 Eminently preventive of shrinkage. 
 Tin .... 55.69 Shrinking component. 
 "Shrank .014." (!) 
 
 That is, an alloy with 44.31 parts of expanding and non- 
 shriuking components, and 55.69 parts of shrinking com- 
 ponents, shrank three times as much as one composed of only 
 40 parts of expanding components and 60 parts of shrinking 
 components ! 
 
 Again, as if in more complete derision of this famous 
 " shrinker," — Townsend's Improved — "Walker's," with an 
 analysis which places it for shrinkage in exactly the same 
 grade of alloys with "Arrington's," 
 
 Silver .... 34.89 "I 39 parts expanding and non-shrinking ; 1 
 Gold 4.14 ) neutral, 
 
 Platinum ... .96) 60 parts contracting, 
 Tin .... . 60.00/ ^ ^' 
 
 " Shrank " o»iZ2/ .002. (!) 
 
 But, strangest of all, " Johnson & Lund," with an analysis of 
 
 Silver .... 38.27 \ 39 parts expanding and non-contracting; 
 
 .81 I 
 
 Gold 81 J IJ parts neutral, 
 
 Platinum . . . 1.34 
 
 Tin 59.58 
 
 Shrank .001+. 
 
 [ 59^ parts contracting, 
 
 Thus, this alloy, which expends only 16 cents — per ounce 
 of alloy — for gold to control the shrinkage of its 60 per cent, 
 of tin to the minimum (.001+), handsomely exceeds "Walk- 
 
74: PLASTICS AND PLASTIC FILLING. 
 
 er's" control of his 60 per cent, of tin, at an expenditure of 94 
 cents — per ounce — for gold; and leaves " Townsend's Im- 
 proved," with its determined control of only 55.69 per cent, 
 of tin, by an expenditure of $1.06 — per ounce — for gold, so 
 far in the rear that the difference can only be viewed in con- 
 trast. 
 
 It seems to me that further comment on such work is need- 
 less. And yet the idea of the index micrometer is, to a cer- 
 tain extent, a good one. 
 
 The " index " instrument which I use for " shrinkage " meas- 
 urements was made by Mr. Henry Coy, — the well known HC, 
 — whose monogram, upon his excellent make of goods, has for 
 so many years duplicated that of S. S. W., and was presented as 
 a contribution from him to the armam.entorium of experimen- 
 tal alloy work. It was made from the copy of Prof. Hitch- 
 cock's instrument used by Dr. Bogue, and loaned me by him. 
 
 By suggestions of Mr. Coy very decided improvements upon 
 the original micrometer were made ; the great desideratum of 
 accuracy of packing is much more perfectly accomplished ; the 
 shape of the circular end of the short arm of the " pointer " 
 was materially altered, as the circle of the original pointer fa- 
 vored largely the heavy shrinkers and condemned uns23aringly 
 the light shrinkers ; a sliding matrix-slot was so arranged that 
 the ingot could be easily and safely removed at conclusion of 
 experiment, that other experiments pertaining to density and 
 strength of alloy might be performed ; and in this improved 
 condition the instrument is well represented in the annexed 
 illustration. 
 
 By this instrument, it is shown that there is relativity be- 
 tween composition and shrinkage ; the heavily tin alloys make 
 amalgams which shrink most notably. If to these alloys gold 
 or copper is added, the shrinkage is lessened in approximately 
 just relation with the amount of non-shrinkers introduced! 
 
 But it is to the measurement of the amalgams made from 
 the heavily silver, tin, and copper ; and silver, tin, gold, and 
 copper alloys that we are now most attracted; for "shrinkage" 
 in connection with these is reduced to " team rifle-practice." 
 
 For this purpose, I now use the two-inch matrix — micro- 
 metric — and direct microscopic measurement. 
 
TESTS FOR AMALGAM. 75 
 
 To one of Queen's Houseliold Microscopes tlie following 
 alterations were suggested by, and made, under the direction 
 of Mr. E. Pennock, to adapt it to this service. 
 
 The stage is altered by elevating the spring-clips to take 
 the plate containing the matrix with the amalgam ingot to be 
 tested. 
 
 A one-half-inch object-glass of wide aperture, which is bet- 
 ter suited for examining opaque objects, is adapted to the in- 
 strument. 
 
 A Jackson eye-piece micrometer is fitted to the eye-piece, 
 and a stage micrometer, ruled to yd-o'^^s and y gL_ths of an inch, 
 is furnished for obtaining the value of the divisions of the eye- 
 piece micrometer. The latter is adjustable by a screw, for the 
 purpose of bringing one of the lines of the micrometer to coin- 
 cide accurately with the margin of the space to be measured. 
 This is, of course, between the free end of the amalgam ingot 
 and the sliding matrix-slot. 
 
 By this instrument and arrangement fine work can not only 
 be done in its aggregate, but the gradation of shrinkage, until 
 completion, can be watched and noted with reliable accuracy. 
 
 Third. Setting Test. — For this test, it is of importance that 
 the exact amount of mercury best adapted to the proper work- 
 ing 'of each given alloy be ascertained. Each sample is then 
 mixed and worked just as it would be in the filling of a tooth. 
 The object is to obtain the possibilities of each amalgam ; but 
 in my present amalgam experiments I have abandoned the 
 " dry-mix " — as it is called — and also the use of warm instru- 
 ments for the introduction of the filling ; but any expedient is 
 permissible for the hastening of " setting." 
 
 The greatest difference conceivable exists in the behavior 
 of difi'erent amalgams under this test; for with some — notably 
 those made from the silver, tin, and gold alloys — teeth can be 
 " built up " in such wise as that they will sustain clasp-work in 
 from thirty minutes to an hour ; while Avith amalgams of mer- 
 cury, tin^ and silver, such manipulation can hardly be per- 
 formed as will permit, first^ of the immediate "building up," 
 and, second^ of the utilizing for clasps, in less than several 
 hours, if, indeed, in less than a day, with perfect safety. 
 
 In mere experimental testing for " setting," the " set " is re- 
 
76 PLASTICS AND PLASTIC FILLING. 
 
 garded as accomplislied wlien tlie filling will take, vnthout 
 necessarily retaining^ a bright, smooth burnish. 
 
 Fourth. Color Test. — By universal consent, I believe, sul- 
 phuretted hydrogen water is used for this test. In my experi- 
 ments I use, for quick results, this water as it is employed in 
 ordinary metallurgic work — full strength; but it is much bet- 
 ter, and, in fact, essential, for the determination of gradation of 
 discoloration of amalgams, that the tests be made with dilute 
 sulphuretted hydrogen water, 1 part to 2, 4, or 6 parts of dis- 
 tilled water. 
 
 In such dilutions the gradual discoloration of the sample is 
 accurately noted. 
 
 Some very strong sulphuretted hydrogen tests, such as solu- 
 tions of sulphuret of potassium, etc., have been suggested, and 
 have been represented as conclusive provers of " superiority " 
 in amalgams. This opinion is not only erroneous in theory, but 
 is very deceptive in fact. So far from being a test of superior- 
 ity and goodness, a powerful sulphuretted hydrogen ''^ color test'''' 
 is one of the best tests for general inferiority and badness. Any 
 amalgam which will not discolor at all in this test should be 
 viewed with much suspicion, and, indeed, it may be regarded 
 as convicted — upon prima facie evidence — of some serious 
 deficiency. The presumption is that the amalgam is " cadmi- 
 umed ;" and that just in proportion as it retains good color, 
 so is it loaded with this tooth-destroying metal. 
 
 "It is very important to know that rather inverse to the good 
 maintenance of color is the real value of amalgam. 
 
 In cases where cavities can be nicely " lined " either with 
 good varnish or good oxy-chloride of zinc, it is better that an 
 amalgam of good maintenance of color be used ; but if the 
 preservation of the toothy as in a lone molar for clasping pur- 
 poses or for mastication, be the prime consideration.^ all expe- 
 rience indicates that an amalgam which will discolor, better 
 accomplishes this end. Therefore, in such cases, and particu- 
 larly if there are " submarine " complications, alloys of silver, 
 tin, and copper should be used in preference to those contain- 
 ing gold, platinum, zinc, or — worst of all — cadmium. 
 
 Fifth. Edge-strength Test. — For the suggesting and devising 
 of this important " test," I must claim for myself the original- 
 
TESTS FOR AMALGAM. 77 
 
 itj. The necessity of good " edge-strengtli " is recognized in 
 connection witli all filling materials except gutta-percha ; but 
 in no other material in which it can be regarded as mainly a 
 physical characteristic^ is it so important as in amalgam. 
 
 In the working of tin, a certain degree of edge-strength can 
 be given by superior manipulation. In the working of gold, a 
 marvellous degree of edge-strength can be given by superior 
 manipulation; while a sufficiency of edge-strength can be given 
 for a majority of fillings by very ordinarily good manipulation. 
 The oxy-chloride of zinc-fillings are not expected to have any 
 sustaining degree of edge-strength, nor to retain for any great 
 length of time even the edge which is first obtained. The zinc- 
 phosphates, though capable of possessing in considerable de- 
 gree this desirable attribute, are quite deficient as at present 
 in tj|ie market. Grutta-percha is accepted as possessing, practi- 
 cally, no edge-strength. Amalgam, therefore, is the only "plas- 
 tic" which can to any extent be depended upon for edge- 
 strength. 
 
 It is this fact, superadded to the recognized need for the 
 quality, which made worh upon this point of such serious im- 
 port to the " plastic-fillers." 
 
 In this, perhaps, more than in any other direction, was it 
 necessary that experimenting should be done with the attain- 
 ment of results which should be unquestionable. 
 
 The usual method of making " buttons," and testing the 
 edge-strength by breaking them with the thumb-nail, was re- 
 garded as evidently unscientific and unsatisfactory, notwith- 
 standing its modicum of sturdy practicality. The instrument 
 shown in the illustration was, therefore, devised. 
 
 Ingots of amalgam for " edge-strength tests " are made of the 
 definite shape and size given by the bevel-edged matrix. Into 
 this matrix samples of the different amalgams are packed as 
 though for fillings ; endeavoring to give to each the greatest 
 edge-strength of which it is capable. After allowing the "test" 
 to harden thoroughly^ it is taken from the matrix and screwed 
 firmly in position by the thumb-screw lever. The chisel 
 shaped punch-rod is then rested upon the edge of the sample, 
 and the rolling-pea is slowly pushed out upon the graduated 
 scale-beam. The indicator shows the point at which " crush " 
 
78 PLASTICS AND PLASTIC FILLING. 
 
 or " fracture " occurs ; and tlius is graded the relative " edge- 
 strength," with its accompanying " toughness " or " brittleness." 
 
 By this test is also graded the relative ratio of '■''setting''^ 
 within the bounds of " burnish possibility." Thus, for exam- 
 ple, a sample of "Townsend's" is packed and allowed to set for 
 fifteen minutes; it is then carefully removed and "tested" with 
 a light rolling-pea. A sample of " Hardman's " is packed and 
 tested also, after having set for the same length of time ; then 
 another sample of " Townsend's" is allowed to set for thirty 
 minutes, and is then tested ; and a duplicate of " Hardman's " 
 is also tested after thirty minutes' setting. It will be seen that 
 by this method gradations may be obtained which will defi- 
 nitely " rank " any amalgam, and that, too, beyond reasonable 
 probability of error. 
 
 Sixth. Tooth-conserving Test. — This, after all, is the grandest 
 test of amalgam. It is the test which can only be done ia the 
 mouth ; it is the test which has been given it in the most try- 
 ing manner, asking of it to " do " when everything else had 
 not done ; asking of it to " stand " when everything else had 
 fallen; asking of it to "save" when everything else had 
 failed ! 
 
 And how has it responded? If /were to say, "nobly!" I 
 might, very truthfully, be regarded as an interested witness, for 
 amalgam has largely contributed to my success in the difficult 
 task of saving everything that had been hopelessly abandoned! 
 
 So I will not testify ! 
 
 Some of the blackened " shells of teeth " that Avere filled 
 with coin amalgam more than forty years ago, testify. The 
 thousands of teeth that have been filled, apologetically .^ testify. 
 
 The hundreds of teeth that have been filled with the assertion 
 and the full belief that they would "last only a year or two," 
 and have lasted ten and sometimes twenty — testify. 
 
 Dentists also testify. In the face of opposition ; in spite of 
 vituperation ; in contempt of malediction ; in defiance of threat- 
 ened professional ostracism, dentists have testified. Admissions 
 of deadly antagonism, without one particle of knowledge or ex- 
 periment, have been wrung from some — that is testimony; 
 the possibility of its utility "in certain cases" has been ad- 
 mitted by others — that is testimony ; good words have been 
 
TESTS FOR AMALGAM. 79 
 
 ventared for it, slanhuise, ever and anon, even by respectable 
 members; it is believed by them "to be valuable as a filling 
 material when used with proper care and discrimination'''' !! ! 
 that is testimony. 
 
 But others have spoken heartily^ out of their love for truth, 
 out of their knowledge gained by 3^ears of experiment and oh- 
 servation. 
 
 Dr. S. P. Cutler says, " Take any mouth or any number of 
 mouths, with decayed teeth in every and all stages of decay, 
 and let any first-class operator fill all decayed teeth on one side 
 of the mouth with gold, and all on the other with best quality 
 of amalgam, say all back of cuspids, the same skill and care 
 being used in both, and await results." 
 
 " In my opinion, based upon observation^ the side of the mouth 
 filled with amalgam, in ten or twenty years, will be found in a 
 better condition than the other," 
 
 Dr. C. 0. Allen says, " If my life and fortune depended upon 
 the saving of a tooth merely, without regard to its appearance, 
 I would fill it ivith amalgam.^'' 
 
 Dr. J, Washington Clowes says, " Thus imperfectly have I 
 discussed amalgam. Conceived in weakness, brought forth and 
 nurtured by empiricism, traduced, maligned, denounced by 
 professionals in high places, malused, abused, and buffeted, it 
 has come to be a power in the land." " Out of weakness it has 
 grown strong, and the very vices of its origin are covered by 
 the mantle of its virtues." " The combination of metals known 
 as amalgam is singular in this : That of all the faults it is said 
 to possess, of all the harm it is said to have done, it is as free 
 and innocent as the child unborn." 
 
 " I am impelled to take up its defense at this time by a sense 
 of duty which I owe to it and to every people, wherever in 
 the wide world the voice of its calumniators has been heard, 
 believed, and had power to alarm." 
 
 " I know of no worthier act than the performance of duty, 
 no higher aspiration than the enunciation of truth, no attain- 
 ment more eminent than professional excellence. By the sense 
 of duty well performed, by the truth fearlessly proclaimed, by 
 the excellent idealized and labored for, I beseech you, brethren, 
 be not henceforth faithless, but believing." 
 
80 PLASTICS AND PLASTIC FILLING. 
 
 This is the sound of the advocates of amalgam. It pours 
 forth from the heart with the earnestness of conviction; it 
 comes from the brain stamped and milled as the coinage of in- 
 telligence ; it has the " ring of the true metal," while the 
 " valuable, if used with care and discrimination^^'' has the feeble 
 tinkle of the truckler to professional prejudice. Amalgam has 
 proven itself to be a notable tooth-saver. 
 
 AETICLE VIII. 
 PBEPABATION OF CAVITIES. 
 
 THE very frequent occurrence, in discussions, of the statement 
 that " cavities are prepared for amalgam with the same care 
 as for gold^'' is significant of the fact that gold preparations are 
 esteemed as essential to the highest future integrity of the fill- 
 ing. In fact, the remark is usually made in that semi-apologetic 
 tone which seems to intimate the presumption that for amalgam 
 the preparations might be thought to be made, ordinarily, after 
 such manner as would be in consonance with the probable in- 
 ferior manipulative ability of the " plastic-filler ; " and it is de- 
 sired that fellow-members shall be aware that, although the 
 filling to be introduced is inferior to those generally inserted, 
 the " preparation " is of that superior order usually indulged in 
 by the speaker. 
 
 The worker in amalgam recognizes that every principle 
 which governs the preparation of cavities for gold fillings is 
 ignored in the preparation of cavities for amalgam. He, there- 
 fore, would not prepare his cavities for amalgam with the 
 " same care as for gold " any more than he would prepare cav- 
 ities for gold with the same care as for amalgam. He prepares 
 his cavities for gold fillings, with care, /or gold, and his cavities 
 for amalgam fillings, with care, for amalgam, without any 
 thought of comparison of the one with the other, because there is 
 nothing in common between the two preparations. 
 
 In preparing for gold, the governing principles result in the 
 making of free ingress to cavities ; of flush walls with antago- 
 nizing bearings ; of retaining grooves and pits ; of cavity shape 
 
' PREPARATION OF CAVITIES. 81 
 
 triflingly larger at mouth than at base ; and in the al^sence of 
 undercuts and overhanging edges ; all is done to the end that 
 the packing of the gold shall be accomplished without danger 
 of interstice between filling material and cavity wall — leakage 
 is the bugbear of the gold-filler. 
 
 In preparing for amalgam, the governing principles result 
 in the making of cavities without angles ; with no flush walls ; 
 few, if any, pits ; with cavity shape decidedly larger inside than 
 out ; with concave undercuts and largely overhanging edges ; 
 in short, he aims to make his cavity a concavity to the extent 
 of his ability. Why is this ? Because he recognizes the sphe- 
 roiding tendency of his material ; he recognizes that it " draws " 
 from angles and from straight walls; he wants to shape it and 
 to place it as it vmnts to stay. Bulging and crevicing are the 
 bugbears of the amalgam-filler. 
 
 In the preparation of cavities for gold, it is taught to remove 
 all decay which is possible, compatible with safety to the pulp. 
 This is done for the double purpose of a firm foundation upon 
 which to rest the filling, and for the insuring of solid packing 
 to prevent leakage. So important is this to the success of gold 
 work, that immediately upon the acceptance of the " leaving 
 of decay " as essential to the proper preparation of certain 
 kinds of cavities — a practice which was fought almost as bit- 
 terly as was amalgam, but which Prof. Arthur pushed to dis- 
 cussion and acceptance with all the energy of strong conviction, 
 — such devices as golden arches made of pellets, concavo-convex 
 disks of plate, etc., were suggested as supports for condensa- 
 tion. 
 
 In the preparation of cavities for amalgam all this is lost 
 sight of — the retaining edges, the deep curves, the "holding 
 power " of properly prepared periphery^ make the mind of the 
 amalgam-worker easy on the score of plug-retention, and he, 
 truly, bestows as much attention, care, and thought upon not 
 removing decay as the gold- worker does upon its removal ! 
 
 In a recent society discussion upon amalgam, it was asked, 
 " What is the theory of the action of amalgam upon the teeth? " 
 The reply of one of the most distinguished of those present is 
 reported to have been that " Teeth are rendered calcified by 
 it," and are " saved by the deposits of lime salts from the fibrin 
 6 
 
82 PLASTICS AND PLASTIC FILLING. 
 
 in the tubules. I have never seen this excessive hardening 
 under gold," This is unquestionably a statement of facts. 
 Decayed dentine is recalcified, very usually under- amalgam ; 
 and, although I have frequently seen exceedingly hard recal- 
 cification — very dark — under gold, yet, the characteristics of 
 the recalcified tissue are suf&ciently dissimilar to warrant me 
 in saying that I have never seen such calcification under gold 
 as I usually find under amalgam. 
 
 With the S. B. Palmer theory of " compatibility," this seems 
 to us, of the " New Departure," as capable of being reasonably 
 commented upon beyond the confines of mere statement of 
 result. Agreeing with Prof. Arthur, that, "in a majority of 
 cases, if the cavity he so filled as to preclude leakage, caries 
 will not progress even though decayed^ dead^ and decomposed 
 dentine be left therein" — I regard gold as a means for the 
 arrestation of decay by this method. 
 
 In teeth of good structure it precludes " leakage ; " it acts as 
 a mechanical barrier to the continuance of that decalcification 
 of dentine which has been proven to be beyond the power of 
 the pulp to prevent ; this being done, secondary calcification 
 takes place. If the matrix — decalcified dentine — is light in 
 color, the recalcification differs but slightly from original 
 dentine ; if the matrix is discolored, — and I have left it some- 
 times very dark, — the recalcification is subject to that con- 
 trol, and I have seen it almost as dark as under some amal- 
 gams. 
 
 In regard to relative "hardness," I have nothing positive 
 to say ; for it is comparatively infrequent that I have to cut 
 recalcified dentine ; but, in my experience, it never has occurred 
 to me to grade recalcification under amalgam as harder than 
 that under gold. I have seen it soft under each, and intensely 
 hard under each. 
 
 But, as I have said, I have never seen such recalcification 
 under gold as I usually find under amalgam. It is this which 
 demonstrates one of the greatest differences between the two 
 materials as filing materials. Take an ordinary cavity in a 
 very soft tooth : the preparation is easily made ; the cavity 
 walls are thick aud sufficiently strong ; either material is well 
 inserted by any one possessing an average amount of skill. 
 
' PREPARATION OF CAVITIES. 83 
 
 Botli fillings look as tliough thej would do good service, and 
 here the equality ends. 
 
 The gold, not liable to tarnish, maintains its appearance of 
 integrity — it is a thing of heauty ; the amalgam, liable to tar- 
 nish, gradually loses its whiteness ; it gradually becomes more 
 and more discolored ; the surrounding tooth-stracture partakes 
 decidedly of this discoloration ; the entire tooth is " shaded ; " 
 it is not a thing of beauty ! But what is the result ? Prof. 
 Arthur says, " If leakage is prevented, etc.," but in a very soft 
 tooth leakage cannot he prevented; it comes through the soft 
 tissue of the tooth itself, and moisture finds in gold an un- 
 changing substance, resisting all approach, an "incompatible" — 
 according to our ideas — ofiering everything but help in this 
 emergency. It usually is not many years before an examining 
 probe can readily be passed between the filling and the soften- 
 ing cavity walls. 
 
 So, in the very soft tooth filled with amalgam, the leakage 
 cannot be prevented, but, coming through the tooth -tissue, 
 moisture finds itself in contact with a material susceptible of 
 change; a material which, instead of resistance, offers decom- 
 posing yielding to approach ; less " incompatible " at first, ac- 
 cording to our ideas, from the metallic standpoint, increased 
 " compatibility " results from the gradual formation of soluble 
 salts of silver, tin, and copper ; these being dissolved, are taken 
 up by the contiguous dentine, which, with its incorporated me- 
 tallic salts^ becomes so in aifinity with the amalgam filling, with 
 its film of " tarnish " — metallic salts — as to insure almost 
 completely harmonious apposition of tooth-bone and filling, ces- 
 sation, practicallj^, of decay, and recalcification, ivith metallic 
 lustre, of decalcified dentine. 
 
 This, the amalgam-worker counts upon ; he requires no firm 
 substratum as a solid resting-place for filling, but places his 
 plastic material, gently, in perfect apposition with the soft den- 
 tine, having faith to believe that in due time both will become 
 hard, and having some definite theory upon which to base the 
 probable realization of his hopes. 
 
 In order to insure success, the amalgam-worker largely con- 
 fines his labor to the peripheral portions of his cavities ; in his 
 obtunding of sensitiveness, he mainly bestows attention upon 
 
8^ PLASTICS AND PLASTIC FILLING. 
 
 the snb-enamel membrane ; in liis cavity shapings, his thoughts 
 are always upon spheroiding, and by these means having made 
 preparations in point of fact, from the manipulative, the thera- 
 peutic, the theoretic, and, by this combination, from the scien- 
 tific standpoint — equal to anything which could be done for 
 gold — he, in addition to all this, is helped by his filling mate- 
 rial, and thus the record is made that teeth can he saved with 
 amalgam which cannot he saved with gold. 
 
 AETICLE IX. 
 TEE MAKING OF AMALGAM. 
 
 IN" the earlier days of this njaterial^ it was the generally ac- 
 cepted method of making, that the desired portion of coin 
 filings should be placed in the palm of the hand, and should 
 have mercury added to it in sufficient quantity to admit of the 
 forming of a plastic mass by kneading it with a finger of the 
 other hand. To do this properly is a prolonged and difficult 
 piece of work. If an insufficient quantity of mercury was first 
 added, and the mass, in consequence, was not plastic enough for 
 proper kneading and for working as a filling, more mercury 
 was added, in small portions, until the mass was of the desired 
 consistence. If too much mercury was, at any time, found to 
 be in combination with the filings, a part was squeezed out by 
 pressure from the finger. In this manner was amalgam made 
 for its first twenty-five years. 
 
 It is now about twenty -five or thirty years since the mode 
 of making which has been referred to, and described, as the 
 " mortar " and " washing " method, was brought to the general 
 notice of the profession by Prof. Townsend. It is not claimed 
 that the. ideas originated with him, but, on the contrary, it is 
 admitted that the formula for alloy and the process of "wash- 
 ing " were both given Prof. Townsend by Dr. Hunter, of Cin- 
 cinnati. I do not know whether these originated with Dr. 
 Hunter; but it has been stated that others were then using the 
 BO-called " improved " formula and method. 
 
 It was but few years — three or four — before the idea of 
 
THE MAKING OP AMALGAM. 85 
 
 alcoholic cleansing was so forcibly attacked that it largely lost 
 its prestige. As early as 1859, it was suggested, by Dr. James B. 
 Garretson, that chloride of zinc should be added to the filings 
 and mercury in the mortar, and that these be rubbed up to- 
 gether and the chloride of zinc be then washed out by water. 
 This made a beautifully white filling, which retained its color in 
 many cases for quite a long time, and which seemed even more 
 preventive of tooth discoloration than of tarnish to the face of 
 the filling. 
 
 For the reason that the thorough removal of the peculiarly 
 disagreeable taste and "feel" of the chloride of zinc was diffi- 
 cult, I instituted a series of experiments — reported in 1861 — 
 which I concluded by the adoption of chloride of sodium 
 (common salt), used practically, as was the chloride of zinc — 
 washed out by water. 
 
 As my experiments progressed in the direction of silver ad- 
 ditions to alloy, the " washing " became less effective in pre- 
 venting discoloration, but cotemporaneously with this the de- 
 mand for " lining " cavities increased, so that in the course of 
 ten or twelve years I had abandoned "washing " as needless, and 
 had instituted "lining" with oxy-chloride of zinc quite uni- 
 versally, especially in front teeth. It remained, however, for 
 Mr. Fletcher, of England, to demonstrate that ■"washing" was 
 absolutely detrimental, as it produced a condition of amalgam 
 which greatly facilitated and increased leakage. 
 
 Immediately upon his announcement of this fact, I made a 
 liiYe of duplicate work upon this matter, and found that my re- 
 sults corroborated his conclusions most positively. After wash- 
 ing, either with alcohol or water, the amalgam would permit 
 leakage in an extraordinary manner, both quickly and in large 
 degree, and this, too, although the mass was not only ordinarily 
 dried with a napkin — as was the custom — but even when it 
 was attempted to make a thorough drying by using several hot 
 napkins consecutively. It therefore is concluded that " wash- 
 ing" — so far from being useful — is positively detrimental. 
 
 In regard to the mortar-make, my conclusions have been very 
 different, for with all changes, and having tried all suggestions 
 modifying this, I yet adhere to it. In Article V. reference has 
 been made to the proposed mixing of alloys with the smallest 
 
86 PLASTICS AND PLASTIC FILLING. 
 
 possible amount of mercury ; that thus the amalgam be made 
 "dry," as it is termed ; that the result be in the form of powder, 
 and that it be then placed in cavities and rendered plastic by 
 working with heated instruments. As this method is almost im- 
 possible of practice in upper teeth, and particularly in difficult 
 and inaccessible cavities, the ingenious devices of,Jirst, amalga- 
 mating by succussion — placing the filings and small proportion 
 of mercury in a little bottle and shaking them together into 
 powder — and, second, moulding the powder into pellets by pres- 
 sure, using for this purpose a small cylindrical matrix and 
 plunger, were suggested by Mr. Fletcher. 
 
 For the requirements indicated, these methods are certainly 
 the best that have ever been offered, but their necessity is based 
 upon the fact that the alloys to be so treated are most largely 
 composed of tin. With this ingredient, it has been shown that 
 slowness of setting, loss of edge-strength, and tendency to 
 spheroiding, have all to be combated, and this work is, un- 
 questionably, aided most materially by using a minimum of 
 mercury ; but, as in the accomplishment of this purpose by this 
 method, an amalgam — even in pellet form — of such consist- 
 ency as to necessitate its manipulation by heated instruments 
 is afforded, and inasmuch as every such complication is disad- 
 vantageous from the operative standpoint of mutual comfort, 
 it has been essayed to arrive at eqvially good, and if possible 
 better, results by methods which will permit of desirable plas- 
 ticity and of cold worlcing. 
 
 Furthermore, it is contended, and, from experience, I think 
 with reason, that an amalgam is better — more thoroughly an 
 amalgam, more homogeneously plastic, tougher, capable of 
 being more readily and more properly manipulated, and capa- 
 ble of producing better "testings" — if amalgamated upon the 
 principle of mercury melting at ordinary terrqjerature. 
 
 In this process, mercury is added to the filings in sufficient 
 quantity to make a plastic mass which shall meet the varied 
 requirements of " plastic-filling." One of the most important 
 of these requirements is that of easy introduction ; and what- 
 ever else may be accomplished by the "powder" form of amal- 
 gam, this certainly is seriously interfered with. Bat, again, the 
 other requirements of quick setting, non-shrinkage, strength of 
 
' THE MAKING OF AMALGAM. 87 
 
 edge, and maintenaDce of color, are all essentials to the aesthetic 
 worker ; and it is for the obtaining of these that the fine work 
 on alloys has been done and is continually progressing. As I 
 have previously intimated, those operators who have used such 
 alloys as Hardman's, Lawrence's, and Standard have found no 
 need for powder-like amalgam ; and, what is more, they have 
 made results, in quantity, with their plastic, easy-working mass, 
 which compare, most favorably, with any of the most excep- 
 tional successes of the "dry-mixed" amalgams. 
 
 Having by the addition of silver counterbalanced largely the 
 shrinkage of the plastic mass, and having by the addition of 
 gold still more controlled it and assured a better edge-strength 
 and a better maintenance of color, it is permitted that we may 
 make the mass of such consistency as will insure that facility 
 of introduction and complete manipulation which has proven 
 itself, in practice, to be adequate to the comfortable saving of 
 dreadfully decayed teeth. 
 
 It is found, experimentally, that in proportion as alloys are 
 good^ so will they tolerate a large admixture of mercury ; and, 
 indeed, it may be stated much more strongly, that they will 
 require a larger relative proportion of mercury for proper 
 working. 
 
 The reason for this is evident ; for, as the easily melted 
 metal, tin^ is replaced by those which are fused with diffi- 
 culty, as silver, gold, and copper, it naturally requires more 
 of the amalgam making component to effect the desired 
 fusion. 
 
 I do not pretend to say that, even with these good alloys, 
 the minimum of mercury, and the working in the powder form 
 with heated instruments, would not produce a filling which 
 might, theoretically, be better than one made with the larger 
 proportion of mercury; but, for pjracticality^ I must strongly 
 urge the latter, as that form of amalgam which will be more 
 conducive to such results as will be most satisfactory both to 
 patients and operators. 
 
 Beside regarding the plastic mass as the best form in which 
 to use amalgam, and the " mortar-mix " as better than the 
 "hand-mix," from the greater cleanliness, facility, and prompt- 
 ness with which the amalgam is made, it is essential to the best 
 
88 PLASTICS AND PLASTIC PILLING. 
 
 result, with any amalgam, that the mix shall be accomplished 
 in definite proportion with one admixture. 
 
 If a certain proportion of mercury and a certain proportion 
 of filings mixed and rubbed together are known to make an 
 amalgam which responds in a superior manner to the varied 
 tests for excellence, it is by all means desirable that the two be 
 placed together and made into amalgam in those definite pro- 
 portions. If a certain definite result is accomplished in a 
 given time by the rubbing together of these two — mercury 
 and filings — at one admixture, the same definite result cannot 
 be accomplished in the same given time by the gradual addition 
 of alternating portions of first one ingredient and then the 
 other. And yet this is the usual manner in which amalgam is 
 made — filings or mercury are placed in either hand or mor- 
 tar, and the other ingredient is added in sach proportion as is 
 thought right. If the mass is too plastic, and is more in quan- 
 tity than is judged sufficient, the surplus mercury is squeezed 
 out, and with it indefinite proportions of metals, which de- 
 stroys the harmony of mixture in alloy just in proportion to 
 its original exactness. If the mass is too plastic, and all is 
 required, more filings are added. If it be then not sufficiently 
 plastic, more mercury is added. Now all the time that this 
 work is being done, another work is doing — the work which is 
 in progress on the part of the ingredients ; that work which 
 eventuates in the proper hardening of the amalgam mass when 
 it is properly incorporated. 
 
 The overheating by combining with too much mercury melts 
 out certain of the ingredients in unknown quantities. If the 
 alloy is a two-metal alloy, combined without regard to test re- 
 sults, of course comparatively little injury will ensue; the ma- 
 terial, not being good, cannot be made very much less good; 
 but in a fine alloy, compounded with great care and in such 
 proportions as give excellent test results, the withdrawal of 
 any proportion of any of its ingredients is, presumptively, det- 
 rimental, and the withdrawal of indefinite quantities of all its 
 ingredients is, as I have said, injurious in degree just in pro- 
 portion to its original excellence. 
 
 The overcooling by addition of too much filings has just the 
 opposite efi'ect; it chills the mercury in such wise as to prevent 
 
THE MAKING OF AMALGAM. 89 
 
 a given amount from, doing its proper work of fusion. This 
 is distinctly shown in the prompt manner in which an insuf- 
 ficiently plastic mass of amalgam will " take up " mercury. 
 Old alloy, long filed, will take up by this unscientific mode of 
 mixing as much mercury as new alloy, freshly filed, which is 
 about one-fifth more than is required to make a good plastic 
 amalgam. This at once transforms an excellent amalgam into 
 a comparatively poor one. 
 
 Therefore, it is directed to prepare amalgam BY weight in 
 such, proportions as have been found upon trial to make tbe 
 mass just right for working in any given case. This does not 
 direct that the weighing shall be by weights^ but by proportions; 
 and it will be noticed, in the weighing of different alloys, that 
 different proportions of mercury will be required for each class. 
 As in the "quality test," this work will at once grade any al- 
 loy, subject to modifying influences — admixtures of cadmium, 
 etc. — which have been indicated; and, governed by these, it 
 will require for first or lowest grade of two metal alloys — tin 
 and silver — about 37 to 39 per cent, of mercury ; for second 
 grade — tin^ silver, and gold — about 41 to 43 per cent.; for 
 third grade — silver^ tin, and copper — about 46 to 48 per cent. ; 
 for fourth grade — silver^ tin, copper, and gold, or tin, silver, 
 gold, and zinc — about 48 to 50 per cent, of mercury. 
 
 This percentage of mercury is given as average, and may be 
 diminished a little for perfectly easy work in very accessible 
 cavities, but must be increased a little for tbat increase of 
 plasticity which is demanded for acceptable working in the 
 difficult and delicate manipulation inseparable from the filling 
 of inaccessible cavities in frail and sensitive teeth. 
 
 In weighing, for the making of amalgam, the usual small 
 brass scales of the jeweler is all that is required, though several 
 devices especially for this purpose are for sale. The desired 
 quantity of mercury for any given " make " should be placed 
 in one scale, and the beam should then be sufficiently depressed 
 upon the side of the alloy by pouring the requisite quantity 
 of filings into the other scale. It will be understood, that for 
 first grade alloys the beam will have to be notably depressed ; 
 for second and third grade alloys the depression will be less 
 and less ; for fourth — or highest — grade alloys the beam will 
 
90 PLASTICS AND PLASTIC FILLING-. 
 
 deviate but slightly, if at all, from the horizontal. From the 
 scales, the mercury and filings can be poured, successively, 
 into the mortar ; and this possibility should be provided for in 
 any piece of weighing apparatus. If the beam is a fixture, 
 the scale-plates should be movable, and in no case should the 
 scale-plates or receptacles for the mercury and filings be se- 
 cured to the beam, as this prevents emptying them in any 
 other way than simultaneously. The scale-plates should be 
 made of material which will not be affected bj^ the mercury, 
 as ivory, glass, porcelain, or brass. 
 
 This use of scales, instead of being troublesome, can hardly 
 fail, upon trial, to be accepted as the easiest and only reliable 
 way for promptly securing accurate proportions in the prepara- 
 tion of amalgam. 
 
 The proportionate quantities of ingredients having been ob- 
 tained, they should be placed in a small ground glass mortar, 
 For this use the porcelain mortar has been recommended and 
 glass mortars condemned ; but this has been from the fact that the 
 glass mortars were used smooth^ and in such it is almost impos- 
 sible to make an amalgam; but if the glazed surface is delicately 
 taken off the inside of the glass mortar, it will prove much 
 superior to porcelain. In porcelain mortars, the face of the 
 mortar discolors most markedly and disagreeably ; the amal- 
 gam adheres in specks upon the sides, and it is impossible to 
 remove it completely. In ground glass mortars, the face is 
 easily kept nicely clean, and the amalgam mass is readily 
 removed without much effort.* 
 
 The pestle should also be of glass, and the glaze may be 
 removed from its bulbous portion. It is also much better that 
 the little knob on the small end of the pestle be broken off and 
 the pestle be inserted into a wooden handle — hard wood — as 
 this gives one more power for making the amalgam.* 
 
 Having the filings and mercury in the mortar, and having 
 carefully removed any particles of amalgam which may be 
 adherent to the pestle from previous makings, the filings 
 should be gradually incorporated with the mercury. This 
 is done by retaining the mercury in the centre of the bottom 
 of the mortar, and by a circular motion, occasionally reversed, 
 
 * Glass pestles are now made which have proved even more satisfactory than 
 those with wooden handles. 
 
- THE MAKING OF AMALGAM. 91 
 
 drawing in tlie filings little by little. This should be accom- 
 plished with sufficient deliberation, and yet with sufficient ra- 
 pidity, a procedure which can alone be acquired by practice. 
 The object gained by this process is, that in this way the per- 
 centage of mercury given will "take up" and make aplastic 
 mass of the given proportion of filings, whereas, if the filings 
 are at once, and without method, mixed with the mercury, it 
 will become chilled, and the amalgam will be hard, dry, and 
 crumbly. 
 
 The rubbing should be both decided and somewhat pro- 
 longed, until a smooth plasticity is imparted to the " make." 
 The possibility of nicely accomplishing this result is the indi- 
 cation which governs the knowledge as to proper quantity of 
 mercury. If this result is attained too easily, there is too 
 much mercury ; if it is not attainable, there is an insufficiency 
 of mercury, and a little more should be added. 
 
 Amalgamation being, to a certain extent, complete, any 
 amalgam adherent to the pestle should be scraped off into the 
 mortar, using a knife or small spatula — of the set of instruments 
 — for this purpose. The pestle is sometimes cleaned by rub- 
 bing it off with the finger, but the use of the spatula is much 
 neater, and will, by practice, soon become habitual. 
 
 The mass is then gathered by the finger from the mortar 
 into the palm of the hand, and is kneaded until it becomes a 
 "button." This may seem a very simple performance, but it 
 is one of the best tests for the plastic-filler. It is almost unex- 
 ceptionable that, as the worker in amalgam takes his mass 
 from the mortar and works it into a " button," so does he 
 grade himself as skilful or unskilful in the working of the 
 material, and so closely does he do this that an observing 
 expert will place him to a nicety. It seems as though all his 
 knowledge concentrates itself upon this little act, just as a 
 singer manipulates his "telling note," and, inversely, igno- 
 rance and incapacity will crop out when one of the uninitiated 
 attempts to handle a "button." It is the aim, then, by strong, 
 energetic, decided effort, to knead partial amalgamation into 
 homogeneous plasticity. The mass is gathered together in 
 the palm of the hand by the forefinger and thumb of the 
 other hand, and is then squeezed and smoothed into commenc- 
 
92 PLASTICS AND PLASTIC FILLING. 
 
 ing homogeneity by a down stroke of the forefinger; then ma- 
 nipulated as before, and again squeezed with the down stroke. 
 It is during this manipulation, oftentimes repeated, that the 
 "crepitation" of an amalgam is heard. This was referred to 
 in the article on " Tests " as " peculiarly pleasing to the ini- 
 tiated," for it is regarded as indicative of an excellent alloy. 
 The short, sharp, decisive cry is something like that produced 
 in the bending of a bar of tin, and with all the testings in 
 which I have engaged, and even in the daily work of making 
 amalgam for actual practice, it is invariably the case that, when 
 it is perceived by one who knows its meaning, the recognition 
 is immediately made manifest by facial expression of approval 
 or by outspoken words of commendation. 
 
 The " button " having been made, it should be held in the 
 palm of the non-operating hand by closing the fourth and little 
 fingers upon it, thus leaving the thumb, fore-, and middle fingers 
 free to aid in operating. This is at first by no means an easy 
 thing for every one to do, but is acquired, without much diflft- 
 culty, by practice, and is of decided importance, as it maintains 
 to the amalgam a degree of plasticity, by warmth, which can- 
 not be utilized if, as is frequently the case, the " button " is laid 
 upon the operating-table, and there cut up into pieces. The 
 amalgam is now ready for insertion. 
 
 AETICLB X. 
 
 INSTRUMENTS FOB THE INSERTION OF AMALGAM 
 
 FILLINGS. 
 
 WITH the idea that experience indicates the employment of 
 few but accurately adapted instruments as conducive to 
 expert manipulation and productive of superior results, I have 
 gradually introduced, discarded, modified, and selected shapes, 
 sizes, and number of instruments until, for daily routine work, 
 I have for the last three years had no necessity for change or 
 addition ; nor have I seen the possibility of any advantageous 
 reduction in number. 
 
 Based upon these conclusions is a set of filling instruments 
 
Ill ill 
 
AMALGAM-FILLING INSTEUMENTS . 95 
 
 for amalgam, and, incidentallj, for zinc-phosphate and gutta- 
 percha stoppings, the patterns for which I have furnished for 
 manufacture during the past year. The annexed illustrations, 
 with descriptions for use, will, I think, afford all needed instruc- 
 tions to insure a satisfactory adaptation of means to ends. 
 
 It will be observed by practitioners who are generally con- 
 versant with instrument forms that I have endeavored to util- 
 ize familiar shapes rather than devise new instruments ; and in 
 this I have almost entirely succeeded. My reason for so doing 
 is, that the habit of use which has been acquired in one direc- 
 tion may be made subservient in other work ; thus the use of 
 the ball-burnisher, having been acquired for the purpose of fin- 
 ishing gold fillings, may readily be made subservient to the 
 packing of amalgam and zinc-phosphate, etc. 
 
 To the grouping and to the ideas of adaptation I have striven 
 to give the impress of originality, and trust that in this I shall 
 have afforded such aid as is desired by the inexperienced, and 
 possibly may have been fortunate enough to give some hints 
 of value even to those of large amalgam experience. 
 
 The set consists of twelve instruments, ten of which, ISTos. 1, 
 2, 3, 4, 5, 6, 7, 8, 10, and 11, are especially adapted to amalgam 
 work, and eight, Nos, 2, 3, 5, 6, 7, 8, 9, and 12, are subservient 
 to incidental and special requirements in plastic filling. 
 
 It must be noted that the set is first divided into three classes 
 ■ — round ends, flat ends, and trimmers or separators. With these 
 three types one is able to meet all indications. These classes 
 are subdivided into 
 
 Round ends. — 1. No. 1. Large ball-burnisher. This is used 
 for crushing and packing the pieces of amalgam which are suc- 
 cessively placed in position — either by thumb-pliers or amal- 
 gam-carriers — in large cavities easy of access. 
 
 2. No. 2. Medium-sized ball-burnisher. Used for the same 
 purpose and in the same manner as No, 1 in medium-sized cav- 
 ities easy of access, and in inaccessible cavities of large size for 
 final packing after the pieces of amalgam have been prelim- 
 inarily crushed by appropriate instruments, — carriers or flat 
 ends, — also for tapping "wafers" (see Article XI.) and smooth- 
 ing fillings upon the articulating faces of teeth, — especially of 
 the lower teeth, — and upper second and third molars. 
 
94 PLASTICS AND PLASTIC FILLING. 
 
 3. No. 3. Small-sized curved barnislier. This instrument 
 is one of varied usefulness and of frequent adaptiveness. It 
 crushes and packs the amalgam in a large proportion of cavi- 
 ties upon articulating, distal, buccal, and labial faces ; and in 
 cavities of all sizes above minimum it is in constant demand. 
 It packs into under cuts, grooves, and corrugations ; it crushes 
 the outside pieces in large cavities — especially buccal — and 
 packs them nicely, using its side ; it smoothes the face of buc- 
 cal, distal, mesial, and labial fillings; removes surplus material, 
 and defines cervical edges of fillings extending below the gum ; 
 " wafers " buccal fillings better than any other form of instru- 
 ment, and becomes, in amalgam work, an indispensable . 
 
 4. No. 4. Yery small " goose-neck " burnisher. This little 
 instrument is used exclusively in the filling of very small cavi- 
 ties. These are usually in the sulci of molars and bicuspids, 
 or upon the necks of teeth, or in the mesial or distal faces of 
 incisors and cuspids. Its peculiar form is eminently adapted to 
 this work, as it is possible to insinuate it dexterously in spaces 
 of very moderate size between teeth, and then so turn it as to 
 compress and pack filling material in the bottom of cavities of 
 a depth which is considerable in proportion to their size of ori- 
 fice. This instrument is one of those which, though not of such 
 frequent use as some others, is, nevertheless, the instrument for 
 which there is no substitute when its services are required. 
 
 As I have spoken here of very small cavities in front teeth, 
 and as it will be some years yet before the filling of such cavi- 
 ties — even in soft teeth — with plastics will become generally 
 accepted as proper practice, I wish here to say that some of my 
 most decided successes during the past ten years have been made 
 by this practice. I have scores of young patients whose elder 
 brothers and sisters had been placed under the best gold work 
 which our own and other large cities afforded, and whose front 
 teeth — particularly laterals — had been filled and refilled with 
 gold until pulp after pulp had died, and tooth after tooth had 
 discolored, — and all this before they were twenty years of age, 
 — whose teeth are of as soft, and even softer structure than those 
 which had been so treated, and who are now from sixteen to 
 twenty years old, and who are 'most m,arkedly reaping the 
 benefits conferred by plastic fillings in "pin-head" cavities 
 
AMALGAM-FILLING INSTRUMENTS. 95 
 
 of front teeth, in tliat they rejoice in hands ome-loolcing teeth 
 containing living pulps. I have found it comparatively an 
 easy task to care for such teeth if the small cavities are filled 
 first with plastics — gutta-percha and "lined" cavities, with 
 amalgam ; for the work is easy and gentle, and thus the little 
 patients are not demoralized. The fillings last as long, and 
 usually much longer than do gold ones ; and thus they do not 
 require so frequent renewal. And in this way, when patients 
 reach that time of life at which they recognize and appreciate 
 the value of beautiful and entirely vital front teeth, they have 
 them in such shape as that they regard them, as worth care and 
 attention. 
 
 I think there is much in this that is worthy the careful, 
 thoughtful consideration of every dentist, and particularly of 
 those who are now in the earlier years of practice. They will 
 have the teeth of the children of this generation — TEETH BORN 
 OF ARTIFICIAL DENTURES ! — under their charge. It will be for 
 them to make the first onset in antagonism to this wholesale 
 loss of teeth, and my experience is, that " compatibility of fill- 
 ing; material with tooth-bone" is the foundation for tooth salva- 
 tion, and that gold is eminently incompatible with 50/"^ tooth-bone. 
 
 5. No. 5. Medium sized, slightly curved, round end. This 
 instrument is used for crushing and packing in all perfectly 
 accessible cavities of onedium. size, and is particularly adapted 
 for " wafering " the faces of articulating fillings. This instru- 
 ment is also the " large-sized probe " which is frequently men- 
 tioned in my pathological papers as proper for carrying all 
 thin fluid medicaments, as hamamelis, oil of cloves, tincture of 
 aconite, chloroform, etc., in the treating of teeth. 
 
 Flat ends. — 1. No. 6 is a short, double convex, spatula- 
 shaped instrument. It crushes and packs the superficial pieces 
 of amalgam in accessible fillings between teeth, where there is 
 ample space, and particularly such wafers as are used for these 
 fillings ; it trims upon articulating faces in occasional cases, but 
 is mainly used as a packer and smoother. 
 
 2. No. 7 is thin, almost flat, slightly curved, and is used, 
 as is No. 6, in places where want of space will not permit of 
 using a thicker instrument ; it is also used as a trimmer in 
 such cases as require No. 6 for a packer. 
 
96 PLASTICS AND PLASTIC FILLING. 
 
 3. ISTo. 8. This is a very useful instrument, and is used in 
 inaccessible places between teetb ; distal or mesial cavities ; 
 upper, or lower teetb; cavities extending to and under the 
 gum. It is particularly adapted to the placing in position 
 of portions of quite plastic amalgam in very inaccessible cav- 
 ities in both upper and lower teeth — distal faces — after which 
 the pieces are to be packed with ISTo. 2. In wafering such fill- 
 ings as these, No. 8 will be found to work admirably ; it is also 
 useful as a smoother and shaper of fillings between teeth, where 
 space will permit ; also as a trimmer upon articulating faces, 
 particularly of the lower teeth. 
 
 Trimmers or Separators. — 1. No. 9. This is a modification 
 of the curved bistoury. It is more useful in zinc-phosphate 
 work than in amalgam ; but it is sometimes the case that the 
 " quick-setters " harden too much for the easy removal of sur- 
 plus material. When this is so, the alternating possibilities 
 of the convex and concave knife edges of No. 9 will become 
 agreeably apparent. 
 
 2. No. 10 is a modified Lord scaler of thin gauge ; the 
 point is rounded so as to prevent undue wounding of the gum 
 in the work for which it is appropriated. 
 
 I have declared myself in favor of " contour filling," and 
 although this conclusion may be unjust to those who " sepa- 
 rate " between good, strong teeth, I must not be subjected to 
 their criticism, from the fact that my work is almost exclusively 
 pertaining to frail, soft teeth. These come to me largely re- 
 quiring complete contouring, oftentimes with two-thirds and 
 even four-fourths I of the crowns gone, and with but little 
 masticating surface generally, — from scarcity of teeth ; and I 
 aim to make as close proximity of articulating faces — mesially 
 and distally — as is possible. 
 
 These thin trimmers or separators are used for the purpose 
 of cutting the thinnest spaces between such crowns, or between 
 built crowns or fillings, and contiguous teeth. No. 10 is espec- 
 ially indicated in such work between incisors, cuspids, bicuspids, 
 and occasionally even as far l^ack as between first and second 
 molars. 
 
 3. No. 11. This is also a modified Lord scaler, but it is so 
 much modified that its suggester would hardly recognize it. 
 
AMALGAM-FILLING INSTRUMENTS. 97 
 
 It, however, becomes well adapted for the work of cutting sepa- 
 rations between molars, both above and below, by the making 
 of the obtuse angle bend. 
 
 I would direct attention to the fact that the instruments of 
 this set are arranged for " universal " working, — right or left, 
 upper or lower; and it is claimed that much greater facility 
 of instrumentation and celerity of operations are attained by. 
 the habit of constant work with few instruments, and the non- 
 necessity for the frequent change incident to " right and left " 
 filling instruments. 
 
 As the complement to the dozen, I have suggested a spatula 
 which, for shape, balance, size, weight, and temper, seems to me 
 to meet requirements more exactly than any heretofore made. 
 If I may judge from the expressions I have already received, I 
 am correct in this, and I therefore counsel, more unhesitatingly, 
 the use of an instrument which has so many rivals. 
 
 In amalgam work, the spatula is never used for its legitimate 
 purpose, — that of mixing the zinc plastics; but it will occa- 
 sionally subserve excellently for smoothing fillings between 
 incisors, particularly of the lower jaw, where space is limited, 
 and where also, from the narrowing necks of the teeth, it is 
 peculiar in its shape. 
 
 Besides the instruments for ordinary use, we have a number 
 of ingenious appliances as aids in difficult cases. These al- 
 most invariably pertain to cavities in upper teeth, less or 
 more inaccessible. The difficulty in such cases is the placing 
 of the amalgam in position, and its subsequent crushing and 
 packing, without great loss from dropping of the material. 
 With the ordinary instruments this is sometimes impossible 
 of accomplishment, and indeed it is, in some instances, exceed- 
 ingly difficult to do even with the best appliances. 
 
 An instrument which is at once simple and effective is the 
 double-end " carrier and plugger," devised by Dr. W. St. Geo. 
 Elliott, — No. 1, — one end of which — the larger — is deeply 
 serrated and filled with amalgam. This is allowed to harden, 
 and, as pieces of fresh amalgam mass will adhere to hard 
 amalgam, they are thus readily carried into position, and 
 crushed with comparative ease. From the fact of this adhe- 
 sion, the instrument is called the " Loadstone amalgam carrier." 
 7 
 
98 PLASTICS AND PLASTIC FILLING. 
 
 The otlier end is serrated. I should prefer a smooth end, like 
 a medium-sized ball-burnisher ; but even as made, it is, I think 
 a very desirable instrument. 
 
 Another device of the same gentleman is that which is illus- 
 trated as No. 2, and is at once ingenious and practical. Upon 
 careful examination, the illustration will give a verj good idea 
 of the working of this instrument, although it is somewhat 
 dif&cult to understand even by description^. Upon the end 
 of the shank is placed, diagonally, a cylindrical hammer-head ; 
 around this is a tube about one-fourth longer than the hammer- 
 head — just the size illustrated. In this tube there is a slot 
 of about one-third its length, and through this slot the neck 
 of the instrument passes. By pressing, with the end of the 
 middle finger, the downwardly inclined end of the investing 
 tube, it is forced out beyond the hammer-head, and thus a 
 receptacle for amalgam mass is made. By pressure on the 
 mass, retaining the finger in place, a portion is forced into 
 the receptacle. It is then presented to the cavity, when, by 
 upward pressure upon the handle of the hammer, it is forced 
 along through the slot, and the amalgam, ejected from the re- 
 ceptacle, is driven into the cavity ; it is then to be packed with 
 any appropriate filler. This is an excellent instrument, and is 
 in harmony with the degree of plasticity of mass required for 
 filling such cavities as it is intended shall be filled by its aid. 
 
 The only carriers which I have seen that rival, in the least, 
 the one described, are those of Dr. H. S. Chase — No. 3 — and 
 Dr. Thomas Fry — No. 4 ; both are ingenious and effective. 
 Of the other carriers illustrated, — Nos. 6 and 7, — they either 
 do not do that which is required, or do it much less easily and 
 efficiently than those more particularly referred to.* 
 
 Another form of carrier is that known as the " Amalgam 
 Director" — No. 5. This is the invention of Dr. E. E. Mul- 
 lett, and consists of a peculiarly shaped spoon, with a light 
 and appropriate handle. It is a very neat instrument, and, with 
 a little experience, will prove a complete preventive to loss of 
 material in the filling of these inaccessible cavities. 
 
 It is as well adapted for carrying hard amalgam as it is for 
 soft mixed mass, and for this reason is the only one at all use- 
 
 * I now regard the double-end spoon-shaped carrier, pattern of Dr. W. C. 
 Foulks, as the best I have ever .used. .See Plate, Fig. A. 
 
the' INSEETION OF AMALGAM FILLINGS. 99 
 
 ful in wafering. It is particularly valuable in "directing" 
 amalgam into buccal cavities both superior and inferior. 
 
 It is not so good for carrying amalgam to cavities upon tbe 
 distal faces of upper teeth as either the Chase or Elliott carriers, 
 but it conduces to cleaner work, and is more frequently advan- 
 tageous than any other carrier. 
 
 In this connection, I should not omit the information that, 
 in addition to many appliances in furtherance, advantageously, 
 of amalgam work, there are also quite a number which are 
 truly curiosities in their way. Some are made with one end 
 about equidistant in form between a toothpick and a sail- 
 needle, and with the other end in the shape of a little cup so 
 attached as to be incapable of subserving any purpose, even if 
 there was any purpose to subserve ; others have ends some- 
 thing like shoehorns, and handles like modern ice-picks ; in 
 short, the singularity of form illustrated by these instruments 
 is only exceeded in degree by the absolute absence of possibil- 
 ity that anything in the way of amalgam working should ever 
 be accomplished by any of them. 
 
 AETIGLE XL 
 THE INSEETION OF AMALGAM FILLINGS. 
 
 AS a large proportion of the alloys which are at present in 
 use will not make amalgams which can be graded even as 
 " good " under testing, it is but reasonable to infer that but few 
 operators have ever worked amalgam that would rank as "ex- 
 cellent " upon its own merits. This being the case, it must 
 equally be presumed that the working of fine amalgam, differ- 
 ing as it does, essentially., from that made from all ordinary — 
 60 tin, 40 silver — alloys, will have to be acquired by nearly 
 every dentist. Even those who have had considerable expe- 
 rience with such amalgams as are made from Townsend's, 
 "Walker's, Arrington's, etc., will find such decided difference in 
 the working of Lawrence's, Hardman's, and " Standard " as will 
 surprise them. And it should also be known that their working 
 of these amalgams must not be regarded as forming any cri- 
 
100 PLASTICS AND PLASTIC FILLING. 
 
 terion as to the possibilities of amalgam work with such material, 
 for, with observation, care, and practice they will soon learn that 
 — as with gold — the most expert manipulator makes the finest 
 results. 
 
 It is too generally believed that an amalgam filling is an 
 amalgam filling no matter what it is made from, how it is made, 
 or in what manner it is inserted ; but this is hardly more cor- 
 rect than it would be to assert that a gold filling is a gold fill- 
 ing. It is true, that the range between extremes is not so great 
 in amalgam work as in gold work, for the difference between a 
 wretched gold filling and an admirable gold filling is so im- 
 mense as to be incredible to any but proficients in such work ; 
 neither is the difference in results between poor amalgam filling 
 and good amalgam filling in the least degree comparable with 
 that which obtains between poor gold filling and good gold 
 filling ; for a good gold filling will save even a soft tooth for a 
 certain length of time, while a poor gold filling may truthfully 
 be regarded, from the first, as a very questionable occupant for 
 a cavity in a frail tooth. On the other hand, the cases now count 
 by thousands in which confessedly poor amalgam fillings have 
 already done longer and better service in frail teeth than 
 equally confessedly excellent gold fillings had done previously 
 in the same teeth. Neither is the range between extremes in 
 manipulative skill nearly so great in amalgam work as it is in 
 gold work ; but this I regard as one of the strongest points in 
 favor of amalgam. It is a fallacy that the profession of den- 
 tistry bases its capability for rendering service to suffering 
 humanity most largely upon the manipulative skill of its mem- 
 bers. In by-gone times this may have been so ; but the capa- 
 bility of dentistry to-day rests most largely — and decidedly 
 most largely — upon the scientific attainments of its practi- 
 tioners in the varied directions of anatomy, physiology, chem- 
 istry, metallurgy, pathology, and therapeutics. Skilful manip- 
 ulation in both operative and prosthetic dentistry can never be 
 underrated, for it leaves its impress, as does the finely-cut die 
 upon the coin ; but it can never again he overrated^ as it has 
 been in the past ; it cannot, in future, grade the position of the 
 dentist ; it will ever be recognized as an essential, but it will 
 be subservient to greater essentials. 
 
THE" INSEKTIOJT OF AMALGAM FILLINGS. 101 
 
 Witli this marked cliange of estimate, the insertion of amal- 
 gam fillings has had, probably, more to do than any other one 
 thing; no other plastic possesses the requisite characteristics 
 for demonstrating so unmistakably that in dentistry, as in 
 other professions, " knowledge is poioery This arises from the 
 fact that, though skill is required in the working of amalgam, 
 and though skill does amply make its mark, it is nevertheless 
 possible to do tooth-saving work with it far more easily than 
 with gold. From this reason it is not needfal that the energy 
 of the student be so exhaustively expended in the direction of 
 finger education ; nor is the list of those who are capacitated 
 for rendering truly creditable and compensating service, neces- 
 sarily, nearly so circumscribed. This insures a loider latitude 
 of henefit to those loho suffer^ and, inversely, it must redound 
 to the elevation of dentistry upon the broad ground of great- 
 est honor to that which gives the greatest good to the greatest 
 member. 
 
 It seems proper to prelude the directions for the insertion of 
 amalgam fillings with certain remarks discussive of the con- 
 dition of cavities preparatory to their introduction. In order 
 that this shall be complete, it must first be stated that " excel- 
 lent " amalgam is at present divided into five kinds — " sub- 
 marine," "usual," "contouring," "front tooth," and ^'facing." 
 Much effort has already been expended for the production of a 
 " universal " alloy ; but, as yet, I have never seen any which 
 made amalgam that met all indications. It appears to be as im- 
 possible to make such an alloy as it is to make a form of gold 
 which will prove equally acceptable in all cases. 
 
 The old-fashioned silver coin amalgam might be regarded as 
 the typal "submarine," for, although no one would be likely 
 ever to use it, it is nevertheless the basal idea for permanence 
 in submarine work. It has been noticed that the black amal- 
 gam fillings done forty years ago have saved the worthless 
 shells in which they were introduced — possibly by the finger 
 of some operator — merely as experiments, until, in some cases, 
 every other tooth has passed away. 
 
 Analysis of these fillings shows them to be composed of 
 about 50 parts mercury, 45 parts silver, and 5 parts copper — 
 approximately; and it is from this start -point, then, that we 
 
102 PLASTICS AND PLASTIC FILLING. 
 
 work for tooth-conservation as a distinguishing cTaaracteristic of 
 amalgam. 
 
 It has also been noted that the most remarkable instances of 
 long maintenance of integrity at the " vulnerable spot " — cer- 
 vical edge — ■ and that, too, under most disadvantageous circum- 
 stances — frail walls, soft structure, beneath gum, under moist- 
 ure — have been attained by these hlach fillings. These, 
 therefore, form the basis for amalgam intended for "sub- 
 marine " work in difficult and inaccessible places. 
 
 I have stated that the thorough amalgamating of coin 
 filings is a protracted and difficult piece of work ; also that 
 tin is a notable facilitator of fusion. It has therefore been 
 deemed advisable to add this metal, in small quantity — from 
 30 to 35 per cent. — to alloy, and to substitute a portion of 
 grain silver — about one-third — instead of using all coin. This 
 makes a "submarine" — 60 silver, 35 tin, 5 copper; — the only 
 positively determined alloy which practically meets the average 
 of combined requirements better than coin amalgam, and an 
 experience of more than ten years gives to it remarkable 
 " tooth-conservation " even under extremely unpropitious cir- 
 cumstances. It discolors reasonably and with desirable prompt- 
 ness, if exigencies demand it, but does not, except in rare in- 
 stances, become as black as coin amalgam, and does not impart 
 to the tooth that greenish hue so distinctive of copper in quan- 
 tity, uncontrolled.* 
 
 Amalgam made from alloys of this nature may be success- 
 fully worked in cavities from which it is impossible to exclude 
 moisture. It can be worked, and with reasonably good results, 
 — the best, I think, which can be made with anything, — in cav- 
 ities which are filled with moisture ; but in such I prefer that 
 the moisture shall be pure water, in which is dissolved suffi- 
 cient carbonate of soda to render it slightly alkaline, rather 
 than the fluids of the mouth, even though these be largely 
 o.omposed of the free flowing outpouring of the sublingual and 
 parotid glands. 
 
 For this reason, I guard, as best as I can, with napkins, against 
 flow of saliva; have the cavity prepared and filled with cot- 
 ton ; make ready, with decided plasticity, my " submarine ; " fill 
 my syringe partially with the alkaline solution, tepid; with 
 * See Appendix, Sec. 4. 
 
THE INSERTION OF AMALGAM FILLINGS. 103 
 
 draw the cotton ; deluge my cavity, and quickly place in posi- 
 tion and compactly insert my filling material. 
 
 The second kind of amalgam is that employed for " usual " 
 work — submarine, one part; contour, two parts. All alloys 
 based upon the " 60 silver, 40 tin," modified by additions of 
 gold and copper, would naturally come into this class. They 
 work with nice plasticity ; set well ; shrink but little, if any ; 
 have sufficient edge- strength ; hold their color well, and offer 
 these varied desirable attributes in compensation for certain 
 loss of "tooth-conservation" which, in usual work, is not so 
 imperatively demanded. 
 
 In working this amalgam — uncombined with other plastics 
 ■^-it is undoubtedly true that just in proportion to the absolute 
 dryness of the cavity, and to the maintenance of dryness during: 
 the thirty minutes required for "setting," other things being 
 equal, will be the perfection and durability of the filling. In 
 these cases, then, the plastic-filler uses the rubber dam when 
 other appliances will not insure sufS.cient dryness. 
 
 It will be noted that this use of the dam takes from it all 
 its horrors, and much that is no more than disagreeable, for 
 there is never any need for passing rubber or ligatures below 
 the gum, and, if a clamp is occasionally employed, its placing 
 and necessary strength of grip are, neither of them, such as 
 would prove inflictive, even to a child. 
 
 The third kind of amalgam is that especially intended for 
 contouring — approximately, silver, 58 ; tin, 37 ; gold, 5. The 
 alloys which make this are those in which quick-setting, ex- 
 ceeding edge-strength, good color, and plasticity of working 
 are the characteristics which it is the endeavor to secure. In 
 these, the copper is excluded, the quantity of gold increased, 
 and platinum ignored. 
 
 This is the field for present work in connection with amal 
 gam. It must certainly be recognized that, in the direction 
 of submarine and ordinary work, the labors of the " New De- 
 parture Corps " have been such as to place the composition of 
 future alloys upon a definite basis, which essentially differs 
 from that almost universally adopted, and which decidedly sus- 
 tains the direction in which had been developed the Lawrence 
 and Hardman alloys, I think that the "Standard" alloy offers 
 
104 PLASTICS AND PLASTIC FILLING. 
 
 tlie nearest approximate to tlie average of all requirements in 
 usual and contour work tliat has yet been attained. The 
 •' quality test " is a touchstone wliich, I believe, will soon serve 
 to weed out inferior and injurious alloys, and compel their re- 
 placement by those which are, at least, much better ; and still 
 the model alloy for contouring is not yet attained. 
 
 Work is constantly being done in this direction ; a work 
 based upon those data which, from previous work, I have been 
 enabled to present to the profession; a work which can be taken 
 ap by all investigators and experimenters at this point, with 
 the assurance that the old landmarks have not been removed 
 without long and careful consideration, and that the new ones 
 have not been set up until they had been subjected to much 
 thought, scientific scrutiny, and experimental observation. 
 
 The fourth kind of amalgam — contour, 1 part ; facing, 2 
 parts — is that used for filling soft front teeth which have been 
 "disked out" or "separated" in such manner as to preclude 
 the use of gutta-percha, and in which the cavities are either 
 too small or are of such shape and position as to interfere with 
 advantageous " lining." 
 
 These alloys of tin, silver, gold, and zinc, while they possess 
 the requisites of very good maintenance of color and of non- 
 shrinkage, are rather slow setters and deficient in edge-strength; 
 but they yqtj well fill the niche for which they are intended, 
 and seem to complete the list of means which enable the plas- 
 tic-filler to enter into such eminently successful competition 
 with the gold-filler in the work of saving the front teeth. 
 
 The fifth kind of amalgam " facing" — approximately, tin, 55 ; 
 silver, 37 ; gold, 5 ; zinc, 3 — is that which at present is least 
 liable to discoloration. Its attributes are entirely in the direc- 
 tion of subserviency to its special requirements. Moderate in 
 its setting ; deficient in density ; wanting in edge-strength, it 
 yet subserves its purpose nicely ; and in a very large majority 
 of cases enables the plastic-filler to make operations — which 
 would otherwise be unsightly — not only acceptable, but fre- 
 quently so natural in their appearance as not to be noticeable.* 
 
 Note. — It will be observed that by three basal alloys, and by "mixing" so 
 as to make other two, a complete succession of amalgams from "submarine" to 
 
 * See Appendix, Section 8. 
 
THE -INSERTION OF AMALGAM FILLINGS. 105 
 
 "facing" are available, and this without the conjoining of copper and zinc in 
 any one of them. 
 
 Amalgam mass, having been made ready for insertion, is 
 held in the palm of the non-operating hand by the closed fourth 
 and little fingers. The palm being turned up and the fingers 
 raised from the button, a portion of amalgam is cut off by the 
 thumb-pliers and is taken by them and — the button being 
 again covered — placed in the cavity. If this be in a lower 
 tooth, the piece will naturally lie in position ; but if it be an 
 upper tooth, the piece will have to be retained in place by one 
 of the free fingers of the hand containing the button. 
 
 The piece should now be crashed by one of the round-end or 
 flat-end pluggers, and thus secured in position ; it must then he 
 tapped with light blows from an appropriate instrument until it 
 is placed in accurate apposition with the walls of the cavity. 
 It has long been the practice to rub amalgam into contact with 
 cavity- walls, and to rub the various pieces consecutively into 
 union with the amalgam already introduced, but the filling of 
 the lower part of two small glass vials will easily convince any 
 one of the decided superiority of " tapping " over " rubbing." 
 A piece of paper should be pasted around that portion of each 
 vial which is to be filled. This prevents watching the prog- 
 ress of the filling and renders the vial, in this respect, more 
 like unto a tooth. Then fill one vial very thorough ly and very 
 carefully^ taking extra pains, by the rubbing and burnishing 
 method. Then fill the other, with only ordinary care, by tap- 
 ping the pieces into position and into homogeneity the one with 
 the other. Scrape off the paper, and it is quite probable that 
 the most skeptical will be entirely convinced as to which is the 
 better method. 
 
 It has been stated that amalgam should be malleted, either 
 by hand or automatic mallet. I regard this as not only unneces- 
 sary, but really objectionable. It is not needful that the blows 
 should be in any degree /orci7;^e, but, on the contrary, it is better 
 that they should be such as would more properlj^ come under 
 the signification of " taps." The consistency of the amalgam 
 should be such as will permit of perfect adaptation of filling 
 ^o cavity-wall by tapping with light blows. - 
 
 In the same manner as is cut ofl" and introduced the first 
 
106 PLASTICS AND PLASTIC FILLING. 
 
 piece, so should the succeeding pieces be cut off and introduced, 
 each piece being united to its predecessors by tapping ; without 
 this precaution, the unions are imperfect, lines of demarcation 
 between pieces are clearly apparent, and leakage is inevitable. 
 
 I^he mass should work quite plastic — generally becoming 
 more and more so as the filling progresses — until the cavity, if 
 it be of ordinary size, is completely filled, when a "last piece " 
 should be enveloped in a fold of chamois skin and squeezed 
 hard, and the wafer thus made be laid on the filling. By crush- 
 ing this wafer into powdery pieces and tapping these into homo- 
 geneity with the softer mass, the setting will be hastened, and 
 the edgs-strength, density, and whiteness of the filling are much 
 increased. 
 
 This process is called " wafering," and will be discussed in 
 the article on " Technicals of Plastic Filling." I have said that 
 if the cavity be of ordinary size, the process of wafering should 
 be used after the cavity is completely filled ; this is so because 
 the size of the filling is not so great as to prevent a sufficient 
 effect upon the whole mass from one wafering ; but if the cavity 
 is very large, or if it is inaccessible, it is better that two or 
 three mixings be made, in small quantity, and that each mix 
 be hardened and set by its own wafer. This will be found par- 
 ticularly advantageous in " building " crowns, or in making 
 large reparations, as contouring amalgam may be so worked by 
 this treatment as to set almost as fast as it is built on, and to 
 become sufficiently hardened in an hour or two to subserve the 
 purposes of mastication or of clasping. 
 
 After the filling is wafered, it should be shaped by trimming, 
 or, if not too hard, it may be smoothed into shape by a piece 
 of soft pine stick. For this purpose, I have pieces of white 
 pine — the softest, and of perfectly straight grain — prepared 
 in slips of six inches long, three-eighths wide, and three-six- 
 teenths thick ; the ends of some are cut to a small round for 
 articulating faces, and the ends of others are cut to a delicate 
 chisel shape for smoothing buccal surfaces and for finishing 
 between teeth. Smaller pieces are adapted to a Cogswell, or 
 other wood carrier, and are thus used in inaccessible places. 
 
 After the filling is smoothed, it should be allowed to harden 
 for ten or fifteen minutes; it should then be burnished, and 
 
GENEEAL CONSIDERATIONS. 107 
 
 smootlied again witTi the stick ; tlien allowed to harden for an- 
 other ten minutes, when it should be finally burnished and 
 finished white with the piece of stick, using, if necessary, a little 
 very finely levigated pumice. In smoothing for final finishing, 
 the stick should be passed over the face of the filling iip or 
 down and not across the filling ; this leaves the lines of finish so 
 that the light will strike upon presenting parallel faces, and 
 thus gives to the filling a much whiter appearance. 
 
 In such amalgams as are controlled by copper and gold, this 
 face will frequently be very well maintained, and I therefore 
 think it advisable to permit the opportunity for their doing so, 
 but if the filling should discolor, it can at any subsequent time 
 be filed or burred ofi", smoothed and burnished. Such amalgam 
 fillings will, almost universally, retain the brightness of this 
 burnished face. . 
 
 It has been sometimes directed to burnish the edges of amal- 
 gam fillings after they have assumed a partial hardness. I can 
 only regard this practice as beneficial with the very poorest 
 amalgams, such as shrink notably, have but little edge-strength, 
 and crevice markedly; but I should equally regard it as posi- 
 tively detrimental to a filling of good amalgam, and detrimental 
 just in proportion to the excellence of the amalgam, A filling 
 made of excellent amalgam should have a clean, sharp edge, 
 of great strength, which should never be broken by burnishing, 
 but, on the contrary, should be allowed to harden thoroughly, 
 and depend upon its own physical characteristics for its integrity. 
 
 AETIGLE XII. 
 
 GENEBAL G0N8IDEBATI0NS PEBTAINING TO 
 AMALGAM. 
 
 IN taking up this subject under the three divisions of: 1. Lo- 
 cal effects; 2. Systemic effects; 3. Possibilities, I cannot 
 help premising that, from my standpoint of observation and 
 experience, the outlook is something so novel to the typal den- 
 tist of the golden age as to appear absurd, and, even more than 
 this, wild and visionary; but I am quite sure that to the 
 younger men, those who have inherited the leavings of the 
 
108 PLASTICS AND PLASTIC FILLING. 
 
 past half century's efforts at saving (?) teeth, those who have 
 to grapple with the daily task of overcoming such apparent 
 impossibilities as would not even be attempted by the most 
 enthusiastic workers in gold more frequently than once a 
 week, and, more than this, to antagonize and conquer presen- 
 tations that would be utterly hopeless in usual practice, or else 
 continue in the wholesale extraction of the present, and help 
 to flood the nations with artificial dentures, my views of amal- 
 gam will, at least, seem worthy of perusal and of thought, 
 and that it will be recognized by them that what has been 
 done so satisfactorily as to have engendered such opinions, 
 might well be tried in vastly more extended fashion, and with 
 the determination to give to the experimentation the benefit 
 of every doubt. 
 
 I feel strongly the truth of the position that amalgam has 
 been so long decried, and is so very meritorious, that I may 
 be pardoned for urging its claim with evident partisanship. I 
 feel that in doing this I cannot do the thousandth part of the 
 great wrong to humanity which has been done by those who 
 have, for many years, so successfully debased it to a low posi- 
 tion. I feel that it has been used by the very men that have 
 abused it, when they could use nothing else, and, that when it 
 has responded to their call most grandly, they have ranked it 
 as secondary the more decidedly, from very fear that its facts 
 might supplant their theories. 
 
 This is strong placing ; but it is none too strong ; for, by 
 this doctrine of subordination of this valuable material, by this 
 teaching that in its requirement of little skill, and in its glori- 
 ous attribute of easy working, it lowered its manipulator and 
 degraded dentistry^ thousands of dentists have been restrained 
 from using it when it would have been the very best thing 
 known for the requirements, and have been stimulated to the 
 employment of gold in cases where it has constantly exhibited 
 the most signal lines of failure even when Avorked by the few 
 who were dignified by the ranking of "eminently skilful." 
 
 Tens of thousands of cavities have been thus filled at fear- 
 ful expenditure of time, suffering, and expense, which ought to 
 have been quickly, comfortably, and economically filled with 
 amalgam. 
 
' GENERAL CONSIDERATIONS. 109 
 
 Hundreds of thousands of teeth have been lost, years before 
 their time, from no other cause than that, in using gold, impos- 
 sibilities were attempted in defiance of incompatibility of ma- 
 terial, and in despite of the insurmountable physical character- 
 istics which precluded its working ; while, with amalgam, these 
 years of comfort could have been bestowed through its nearer 
 approach to compatibility, its peculiar tooth-saving property 
 of forming soluble sulphides, and the physical characteristics 
 which permit its easy working under most disadvantageous 
 circumstances, and in most inaccessible cavities. 
 
 Through the dogmas of the superiority of gold as a filling- 
 material and the elevating of its working to the position of 
 "standard for excellence," and of the inferiority of amalgam 
 as a filling material and the degrading of its working to the 
 position of " standard for incapacity," millions of teeth have 
 been needlessly sacrificed^ and their places filled with those 
 cunning devices of quartz, feldspar, and kaolin which are so 
 appropriately designated — substitutes. 
 
 My voice is given in antagonism to such teaching and to 
 such practice with full confidence, born of years of severe 
 testing, that a change cannot, by any possibility, produce any 
 more discreditable results ; and with a firm hope that it may 
 give comfort, health, and teeth to those whose fathers and 
 mothers have lost all these at the hands of first-class accepted 
 dentistry. 
 
 1. Local effects. — As I have intimated, in previous articles, 
 the local effects of amalgam are not altogether what we would 
 desire ; but, as I have also stated, most emphatically, they are 
 in great degree eminently desirable. It therefore behooves 
 us to discuss, clearly and dispassionately, this important matter 
 in its perfectly tangible bearings. 
 
 I desire that it shall be understood that I regard it as need- 
 less now to discuss, at any length, the peculiarities pertaining 
 to ordinary amalgams ; for it is a principal object with me to 
 give such information regarding " plastics " as shall force all 
 ordinary materials from the market, unless they are offered as 
 such. 
 
 While this arrangement will exclude the vast majority of 
 amalgam alloys at present manufactured and used, it will yet 
 
110 PLASTICS AND PLASTIC FILLING. 
 
 permit the retention of some that are worthy of limited con- 
 tinuance, at least until they are replaced by various makes 
 which shall possess generally good characteristics. 
 
 But it will also permit the retention of some which are given 
 as possessing the very objectionable distinguishing characteris- 
 tic of decided tendency to discoloration. This peculiarity, then, 
 must be accepted, with its concomitant tooth discoloration^ at its 
 precise valuation ; it must be viewed as unfortunate that we 
 have not yet attained any non-discoloring amalgam which 
 we can positively declare to be as tooth-saving as those which 
 freely discolor ; but it must also be taken as partial compensa- 
 tion for this, that we have succeeded in establishing the remark- 
 able control exercised by zinc and gold over this discoloration, 
 and that such amalgams are notably creditable as tooth-savers. 
 
 It must be recognized that if an amalgam which discolors - 
 as, for instance, made from alloy of silver 60, tin 35, copper 5 — 
 is chosen as a filling material, its local effects are regarded as 
 such as overbalance in good that which is admitted as bad. It 
 works plastic against frail walls ; it works as a submarine ; it 
 sets with desirable' celerity ; its shrinkage is infinitesimal; its 
 edge-strength is good. All these are, indisputably, desirable 
 qualities ; but it permits the formation of sulphides, and in so 
 doing produces two results — the filling becomes darkened and 
 presents an unsightly appearance, and the tooth assumes a dark- 
 ish hue, sometimes even blue-black, which is also eminently 
 disagreeable to view. But, again, this very process is the saving 
 of the toothy and it therefore becomes simply a question of ^itil- 
 ity vs. beauty., which, it seems to me, could in every instance 
 very readily be promptly and satisfactorily settled between pa- 
 tient and operator by a plain presentation of facts. 
 
 Another local effect is the occasional induction of galvanic 
 electricity by contact with other metal. This is most usually de- 
 veloped when such contact is made by touching fillings with 
 pins, needles, metallic toothpicks or forks, — either steel or sil- 
 ver, — and the results vary in degree from merely making a 
 peculiar taste, galvanic, through the entire range of sensation 
 from disagreeable to intensely painful — a shock. 
 
 When this occurs, the filling should be removed and an in- 
 sulating medium — either zinc-sulphate, varnish, oxy-chloride, 
 
GENERAL CONSIDERATIONS. Ill 
 
 gutta-perclia, arnica court-plaster (water-proof), or any equiva- 
 lent to tliese — should be so placed as to cut off the sentient 
 conductivity, and thus preclude such liability. 
 
 This effect is quite liable to be produced from contact with 
 the clasps or plate of artificial dentures — gold — and is some- 
 times, though rarely, difficult of prevention. It is in some 
 cases readily obviated by so filing the plate as to preclude its 
 touching the filling during the insertion or removal of the work 
 and during mastication. 
 
 If the unpleasant effect is due to contact of clasp with fill- 
 ing — either in clasp teeth or adjoining teeth — the means for 
 prevention are more complex, less positive, and require more 
 careful consideration. Regarding difference in potential and 
 hrightness of metallic surface as the combining circumstances 
 which, under peculiar condition of oral fluids, produce this re- 
 sult, the first effort should be the removal of brightness. 
 
 This is done by oxidizing the clasp by heat, and by " facing" 
 the bright- surfaced amalgam with a thin layer of *' submarine," 
 mixing a small pellet of this kind of amalgam and rubbing it 
 on those faces of the filling which are touched by the clasp, 
 and then removing it to original contour as the thinnest possi- 
 ble film is sufficient ; or, by coating the inside of the clasp with 
 a mercurial covering by rubbing upon it a small portion of 
 amalgam, which if done carefully, so as to. impinge upon no 
 part of the work except the inner portion of the clasp, will 
 not spread, neither will it enter into the substance of the clasp 
 sufficiently to be detrimental ; or, by changing the location of 
 the clasp and securing to another tooth ; or, by using silver for a 
 clasp, leaving it darkened from the blow-pipe ; or, by changing, 
 if possible, the filling material to some other, though less relia- 
 ble and less durable plastic; or, as a final resort^ if "clasping" 
 is a necessity or a very great comfort^ the devitalization of the 
 pulp of the clasp-tooth. 
 
 This latter consideration is one which it is supposed will 
 be subject to that recognition of contingencies — probabilities 
 and possibilities pertaining to pulpless teeth — which, with the 
 knowledge of the present day, are so accurately reduced to 
 .debatable propositions. In mouths where this galvano-elec- 
 tric effect is very decided, it will occasionally be noted that the 
 
112 PLASTICS AND PLASTIC FILLING. 
 
 contact of small pieces of amalgam with gold fillings will pro- 
 duce a like effect. Thus, the dropping of debris during the 
 introduction of amalgam fillings, or the making of Contact 
 during the rinsing of the particles from the mouth, will oc- 
 casion more or less decided starting on the part of the patient, 
 and will require the desired explanation. In filling under 
 rubber-dam, this difficulty would, of course, not occur ; but in. 
 napkin filling, the napkin should be so arranged as to secure, if 
 possible, the catching of all dropping filling material. 
 
 A third effect is like unto this second, but is occasioned from 
 the fact that a jiUing of different metal, having marked differ- 
 ence of potentiality (^usually gold), is so inserted — disconnected, 
 not touching — into the same tooth or an adjoining tooth as to he oc- 
 casionally connected hy tongue, lijy, or cheek connection. When- 
 ever this connection is made — usually during mastication — a 
 shock of sufficient severity to cause pain and starting is felt. 
 This is cured, either by thoroughly amalgamating the face of 
 the gold filling, or, if in one tooth, by cutting away between the 
 two fillings and making them join, using either amalgam or gold 
 for this purpose, as is indicated either from considerations of 
 appearance or ease of manipulation ; if it arises from fillings in 
 two teeth, one of the two fillings may be removed and replaced 
 with a like material to the remaining filling. I should, of 
 course, advocate the removal of the gold filling and its replace- 
 ment either with tin, gutta-percha, or amalgam, according to 
 circumstances, as I should suppose the considerations which 
 prompted the introduction of amalgam in one of the cavities 
 would outweigh the objections which might pertain to the use 
 of one of the other materials mentioned. It will be noted that 
 effects like these could onl}- occur in wholly vital teeth. 
 
 A fourth effect is a species of metallic salivation due to action 
 through the "gustatory" reflected through the "nutrient" of 
 the salivary glands. This is a very rare occurrence, though I 
 have met with a few cases of it. I have always classed it as 
 physiological rather than pathological action, and regarded it 
 as similar to the effects occasionally produced through the 
 optic and auditory nerves at the sight or mention of certain 
 kinds of food. This effect is sometimes of but short duration 
 — a few days — and, as the faces of fillings lose their bright- 
 ness, it gradually passes away. Having noticed this, I act 
 
GENERAL CONSIDERATIONS. 113 
 
 upon tlie hint, and in cases where it is persistent, and in which 
 the faces of fillings maintain good color markedly, I remove 
 them and replace with amalgam which discolors, carefully 
 lining the cavities so as to prevent tooth discoloration. 
 
 A fifth effect is that of giving rise to a had taste; this is even 
 more rare than the preceding one, and does not occur more fre- 
 quently than once in from five hundred to eight hundred 
 mouths. In every instance, except 07.ie, which I have seen of 
 this condition, the teeth were of that kind in which gold had 
 been tried by various operators of acknowledged skill, with 
 anything but satisfactory results, and in the one exceptional 
 case I heard that a most extensive and elaborate line of gold 
 work was finally resorted to. In these cases I have removed 
 the amalgam and resorted to gutta-percha, oxy -chloride of zinc, 
 and zinc-phosphate fillings with the requisite renewals. 
 
 A sixth effect is an irritation of the fauces, throat,, and larynx, 
 which, while it is not primarily dependent upon the presence 
 of amalgam, is nevertheless much less amenable tO' treatment, 
 while numbers of large amalgam fi,llings are in th©' mouth. In 
 an amalgam practice of twenty -five years, and with an experi- 
 ence in more than five thousand mouths, I have met with but 
 two cases of this kind. In both these cases serious bronchial 
 trouble was previously constantly existent,, but was decidedly 
 less controllable under amalgam irritation than without it. 
 
 In both these cases I removed the amalgam and refilled with 
 gutta-percha and oxy-chloride, and, more recently, with zinc- 
 phosphate, and in both instances with relief to the patient. 
 
 It is more than probable that the vast majority of prac- 
 titioners would pass an entire lifetime without meeting any 
 such cases as these I have last referred to, but it is well to 
 know that idiosyncrasies exist in which such things can occur, 
 in order that one may be prepared to meet them should they 
 happen to present themselves. 
 
 As for the other local effects, which are frequently charged 
 to amalgam, such as pulp-devitalization, periodontitis, alveolar 
 abscess, exostosis, and necrosis, I must say, most, decidedly, 
 that I have never met with an instance in which any of these 
 conditions existed with amalgam fillings as concomitants, and 
 in which I could not think that it would probably have oc- 
 8 
 
114 PLASTICS AND PLASTIC FILLING. 
 
 curred, under similar circumstances, in connection with any 
 other metallic filling material. 
 
 2, Systemic Effects. — I have already spoken of the discus- 
 sions which I asked from the Pennsylvania Association of 
 Dental Surgeons almost twenty years ago. It may be sup- 
 posed that, as I had been for six years directing close attention 
 to all such matters as could be pretty well settled in that space 
 of time, I would have especial interest in the views of my 
 fellow-members upon a subject of such grave moment, and 
 of such difficulty in establishing data hy one observer^ as that of 
 the systemic effects of amalgam fillings. 
 
 I had already conversed with many of the elders of den- 
 tistry, and had found that, without exception^ those who had 
 had experience, either limited or extended, were alike positive 
 in the denial of any such systemic effects as could be attributa- 
 ble to mercurials^ while I had also found that the few who " be- 
 lieved " in this possibility, were also, without exception, either 
 avowedly reiterating the views of those in whom they had 
 confidence, but without having any personal knowledge in 
 relation to it, or were openly hostile to its use, without ever 
 having investigated its merits or demerits to the extent of even 
 one filling. 
 
 , In referring to the proceedings of the meeting of April, 1861, 
 reported in " Cosmos," May, 1861, I find that I expressed thus 
 early in my work the opinion that, while it was " barely possi- 
 ble " an idiosyncrasy could exist in which amalgam, per se, 
 might be injurious, it was, nevertheless, a thing which I had 
 never seen. 
 
 I quote briefly to show the collateral basis which was, upon 
 that occasion, given me, and which I regarded as substantiatirvg 
 my own opinion sufficiently for all practical purposes. 
 
 Dr. C. Newlin Pierce, who opened the discussion, said, in re- 
 gard to amalgam ptyalism, that it was a thing of " so rare an 
 occurrence, that he believed the profession had never heard of 
 but one practitioner who thought that that result was produced 
 by amalgam." 
 
 Prof. T. L. Buckingham said "he had never seen a case of 
 salivation frorri its use, and had doubts about its ever having 
 produced ptyalism-" that mercurial effects were "influences 
 
GENERAL CONSIDERATIONS. 115 
 
 produced througli tlie general system ; but he did not tliink 
 amalgam fillings would produce these effects." 
 
 Dr. J. H. McQuillen said that " in an experience of fourteen 
 years he could not recall a single instance of necrosis of the 
 jaws, ptyalism, etc., of which others assert that they have seen 
 so many ;" and that while he recognized the fact of idiosyn- 
 crasies in which the smallest quantity of certain medicinal 
 agencies is followed by untoward results, and would not, there- 
 fore, offer his negative testimony as positive proof, yet "his 
 own experience had made him look upon those who assert 
 that they have seen so many cases with considerable doubt as 
 to the value of their judgment or opinions as reliable diagnos- 
 ticians." 
 
 Dr. C. P. Fitch said, "in regard to its toxical or injurious 
 effects upon the system, he was inclined to question, if not 
 wholly doubt, any such influence, and concurred in the views 
 advanced by Dr. McQuillen, that he had yet to see the first case 
 of alveolar abscess, ptyalism, etc., due to the presence of mer- 
 cury in the amalgam." 
 
 Dr. J. M. McGrath testified for himself and for his father, 
 who had had an amalgam experience of ten or fifteen years, 
 that as yet they "had never seen any bad effects resulting, such 
 as had been ascribed to its use by many practitioners." 
 
 Thus it was that I was fortified by the combined testimony 
 of gentlemen whom I esteemed as conscientious observers, and 
 for whom I had much regard both socially and professionally. 
 
 It now remains for me to add the testimony of almost twenty 
 years more of increasingly acute scrutiny, with the assertion 
 that during all my amalgam experience I have never seen one 
 case of mercurial ptyalism, mercurial periostitis, mercurial ne- 
 crosis, or of the slightest symptom which could reasonably be 
 ascribed to mercurial action. I have had cases of asserted mer- 
 curialization by the score brought to me. I have treated them 
 experimentally with chlorate of potassium to demonstrate its" 
 utter impotency, and have then cured every case without the use 
 of any anti-mercurials, and have left the teeth refilled with 
 amalgam. If anj^thing more convincing than this is required, 
 I have it not to offer. And yet the cry of mercurial ptyalism 
 still continues. It is repeated not only by medical men, for 
 
116 PLASTICS AND PLASTIC FILLING. 
 
 wliom we must have the needed leniency, but it is stated boldly 
 and persistently by dentists ; by men who have, at least, local 
 reputation, and are thereby capable of doing harm. But I wish 
 it to be noted that no man of reeord^ either scientific, literary, 
 or professional — beyond the making of a good gold filling — • 
 can be found to-day who will commit himself by the assertion 
 that, from observation and experience^ he believes amalgam 
 fillings are liable to produce mercurial ptyalism, and are, there- 
 fore, unfit to use in efforts for saving teeth. 
 
 3. Possibilities. — With this theme I am filled with svTch 
 thankfalness at the knowledge of these, and with such grati- 
 tude that my professional career has been in the pathway 
 opened to me by them, that I long to tell, in one word^ of the 
 possibilities of the various amalgams;, it seems to me as though 
 there was but one word which could express it, and that is 
 fulness. 
 
 Of all the other filling materials, there is no one which cov- 
 ers a tithe of the ground in dental demands that is covered by 
 amalgam when used with a knowledge of its possibilities. Far 
 more than this, I most unhesitatingly assert that, in a practice 
 which shall save e^erj tooth and root that offers which can be 
 saved advantageously, amalgam will enable an operator to pro- 
 duce more satisfactory results — gjading these from an average 
 of the varied stand-points of beauty, permanency, comfort, econ- 
 omy, and utility — than all the other filling materials combined. 
 
 It may well be regarded that I would not make any such 
 statement as this without much consideration ; and it may well 
 be admitted that I have had an experience which has given me 
 ample data upon which to base an opinion ; and it is, therefore, 
 upon the combined strength of reflection, experiment, and ob- 
 servation that I have ventured the position. 
 
 The possibilities of amalgam ; it is an easy thing to tell of 
 its possibilities, but its limits — for it has limits — are not so 
 readily defined. It can take care of almost anything in den- 
 tistry; and it really seems as though its possibilities were more 
 and more demonstrable, just in proportion as the result desired 
 seems more and more impossible of accomplishment. The things 
 which are easy to do with gold are easier done with amalgam. 
 The things which are hard to do with gold are easily done 
 
GENERAL CONSIDERATIONS. 117 
 
 with amalgam. The things whieh are exceedingly difficult to 
 do with gold are not difficult to do with amalgam. The things 
 which are almost impossible to do with gold are not difficult 
 to do with amalgam. The things, by the dozen, which are im- 
 , possible to do with gold are not very difficult to do with amal- 
 gam. And to do well, too ; to do in such wise as that they 
 shall be eminently useful, durable, comfortable, and satisfac- 
 tory; to do in such wise as that the recipients shall, after years 
 of trial, point to them as proofs to others that they, too, can 
 enjo}?" such benefits. 
 
 And this is the material that for fifty years has been stigma- 
 tized as base; frowned upon as low; tabooed as unworthy the 
 notice of skilful men ; disgraced as the token of incapacity and 
 quackery. Is it not time that this thing should be ended ? Is 
 it not time that its serious investigation should be undertE^ken 
 by the coming men of dentistry ? 
 
 Ordinary Cavities. — It has, for so long a period, been regarded 
 as the proof of in-competeney that an operator should even 
 think of filling ordinary cavities of decay with anything but 
 gold, that I deem it of exceeding importance that I should pre- 
 sent this subdivision of my subject with that precision and de- 
 cision to which I esteem it entitled. 
 
 It has been a systematic thing with me to do so for many 
 years, for I was early impressed with the fact that this fallacy 
 was probably, of all others, the most pernicious. 
 
 Who would think of allowing a small break in a dyke to 
 become an enormous crevasse before trying means for its arresta- 
 tion which had been demonstrated to be equal to extraordinary 
 emergencies. 
 
 Who would think of allowing a small fire to increase in size 
 until it should demand the services of a steam fire-engine, if one 
 had the engine in readiness to extinguish the flames in their 
 incipiency ? 
 
 Who but an old school dentist would order that a small cav- 
 ity in a soft, young tooth should be filled and refilled with gold, 
 until, as filling after filling dropped out, the decay had pro- 
 gressed to such extent as to render it impossible that it could 
 be filled with anything but amalgam? 
 
 And more than this, who but an old school dentist would 
 
118 PLASTICS AND PLASTIC FILLING. 
 
 make obedience to this order the test for capacity and for ^''respect- 
 ability " as a dentist ? It is too late for the premises in these 
 questions to be disputed ; such practice is not onlj advocated, 
 but it is ordered. Such results are not problematical; thej are 
 the usual, almost invariable results of such practice. ^ 
 
 And deviation from this rule has always brought contempt 
 upon the man who deviated, that he might save teeth, from all 
 the members who were regularly recognized as " most respect- 
 able." This has been the tone of the vast majority of practi- 
 tioners ; it has been the tone of the society discussions ; it has 
 been the tone of the lecture stands ; it has been the tone of the 
 journals, both small and great — and thus it has been made the 
 tone of the Profession of Dentistry. 
 
 It is a blessed thing for the patients that a few men have de- 
 viated from this practice, and in despite of deviation have had 
 the strength to swim ; for the most of those who have done so, 
 have been forced under incontinently. 
 
 It is a blessed thing for the salvation of teeth, and for the 
 consequent health and comfort of this rising generation, that 
 the appeals from those who have thus '■^departed'''' from these 
 old time landmarks, are arousing the members to a sense of the 
 need for inquiry, investigation, and experimentation. 
 
 I trust, and firmly believe, that it will prove a blessed thing 
 for dentists and for dentistry. I therefore teach that the or- 
 dinary pin-head cavities are those in which the work of saving 
 teeth is to be commenced; that it may with propriety be inferred 
 that a material which will do well in emergent cases will also 
 do well in the control of trifling lesions ; that a material which 
 is easy of manipulation will be less demoralizing in the using, 
 to the young sufferer, than would be a material requiring great 
 skill and persevering labor on the part of the operator and 
 commensurate quiet endurance upon the part of the patient; 
 that a material which will average more durable work than 
 gold, in difficult cases, may properly be accredited with the 
 capability for making more durable work than gold, as its 
 " average," in easy cases ; that thus it is but reasonable to de- 
 duce that a marked increase of successful effort would result 
 from the employment of amalgam in place of goM in such or- 
 dinary cavities as are so situated as to require a filling material 
 
* GENERAL CO]Sr«IDERATIONS. 119 
 
 possessing the physical characteristic of ample resistance to at- 
 trition during mastication. 
 
 It was in furtherance of this view that I spoke as I did upon 
 the occasion of the presentation of the " New Departure " prin- 
 ciples and practice, saying,' "Front teeth, par excellence^ are 
 filled and refilled with gold, as the best that can be done, i*ntil 
 pulp after pulp dies, tooth after tooth becomes discolored and 
 crumbles away, root after root is extracted, and plate after 
 plate is inserted. This is stereotyped practice^ and I defy con- 
 tradiction of the statement." " / think that a liberal allowance 
 of gutta-percha and amalgam fillings in these very teeth, while 
 yet the cavities are only pin-head cavities^ would be a step. in 
 advance of this^ 
 
 " This is still talk; it makes quiet; but it is what I have come 
 to-night to say." 
 
 Large Cavities. — It would seem to require no argument to 
 show that in proportion as cavities increased in size, so would 
 the demand increase for such service as had proven efi'ective for 
 the retardation of the loss of tooth-tissue in teeth largely 
 affected by caries. It is nevertheless true that positions 
 already begin to multiply which render the employment of 
 amalgam in these cases additionally advantageous. With 
 every grade of cavity enlargement, the labor of introducing 
 a gold filling becomes greater in quite accurate ratio, while a 
 notable difference in size of cavity makes but little, if any, in- 
 creased labor attendant upon the introduction of amalgam.. 
 The expense of gold filling is also quite in consonance with 
 the size of the filling — relativity of position being conceded 
 — while this is but very little changed in the use of amalgam,, 
 whether the cavity be " ordinary " or " large." The conduetiv- 
 ity of a filling is to be considered as detrimental in exaict pro- 
 portion to pulp approach, and, in this regard, amalgam., with 
 its comparatively low conducting power, gains in superiority 
 over gold with the loss of every successive stratum of dentine.. 
 Thus, on the varied score of tooth-conservation, saving of labor 
 and of time, saving of expense and saving of pulps, amalgam, 
 presents its claims of superiority to gold for the filling of larg& 
 cavities of decay. 
 
 Enormous Cavities. — To such patients as have had experience 
 
120 PLASTICS AND PLASTIC FILLING. 
 
 in the filling of enormous cavities, as demonstrated by tlie two 
 schools of gold and plastic dentistry, any discussion of the 
 methods and results seems purely ridiculous. I cannot place 
 it better than it was done by one of my patients who had 
 enjoyed more than a decade of years of each kind of practice 
 after he had arrived at an appreciative time of life. He said, 
 " If one lived five or six thousand years, and it had been posi- 
 tively demonstrated that it was a great deal better to fill teeth 
 with gold, I might think of returning to that kind of practice, 
 hut for this paltry seventy years^ give me plastics! " 
 
 This is the view from the patients' side of the question ; and 
 is it to be supposed that their comfort, their time, their health, 
 their strength, and their teeth are of more importance to their 
 dentists than to themselves ? And yet, this is the dental view, 
 and so the teachings continue that it is better to fill " enormous 
 cavities" with gold. 
 
 It is conceded that it is exceedingly difficult to do, but, if 
 well done, it is a proof of superior skill; it is conceded that 
 the expenditure of time is vastly greater with gold than with 
 amalgam, but it is taught that the difference in result is pro- 
 portionately better ; it is conceded that the expense is threefold, 
 fourfold, tenfold, that of amalgam, but that with this it is com- 
 pensating^ and eminently so ; it is conceded that in this work 
 the drain upon the vital force, of both patient and operator, is 
 something fearful to contemplate, but it is said that the beauty 
 and utility of that which is produced is worth it all. 
 
 Now, I ask close examination of all this ; I ask long and 
 careful experimentation in regard to this; I ask that it shall 
 be done with knowledge as its basis, throwing aside that easy 
 soother of conscience, that salve of professional pride, that 
 facile cover for ignorance which has been so frequently, and 
 with such complacent suavity, referred to as "judgment." I 
 ask that there shall be no more of this perversion of language. 
 I would have it admitted that without knowledge there can be 
 no "judgment;" and I would have it felt, and earnestly felt, 
 that in this matter all should recognize the power for good 
 which would ensue from the combination of knowledge and 
 judgment. 
 
 I have worked long and hard to demonstrate the fact that 
 
GENERAL CONSIDERATIONS. 121 
 
 the weight of evidence is in favor of the filling of enormous 
 cavities with amalgam instead of gold, I have taken dentures 
 by the hundred which had been abandoned, by both patients 
 and operators, upon the score of utter worthlessness, upon which 
 months of time, hundreds of dollars, and mountains of agony 
 had been expended, with no other return than repeated, signal 
 failure, and with plastics, and mainly amalgam, have kept them, 
 SATISFACTORILY, in working order, year after year. 
 
 That which has been done can surely be more easily done 
 again. With all the guiding experience of the past, with all 
 the improvements in composition, preparation, adaptation, and 
 manipulation, it will be found that but little inquiry will be 
 needed to prove, first^ that, as a mass, enormous gold fillings are 
 not compensating^ especially to patients, and second, that a prop- 
 erly composed, properly prepared, and properly introduced 
 amalgam, will prove, in truth, an advantageous " royal metallic 
 succedaneum." 
 
 Entire Crowns. — It is quite frequently the case that caries 
 continues progressing in despite of all efforts, local and consti- 
 tutional, operative and medicinal, until the crowns of teeth are 
 either completely destroyed or are rendered so frail as to be 
 broken off during mastication. It is also very frequently 
 noted that, although decay still progresses until the dentinal 
 portion of the roots is almost gone, the cemental portion main- 
 tains its ijjtegrity in a remarkable manner, and thus, remains 
 of roots are in position for fifteen or twenty years after their 
 crowns have been lost. 
 
 It is these facts which have led to the practice of "utilizing 
 roots," as it is called, for the purpose of " pivoting," " grafting," 
 or "building on" crowns. 
 
 Various methods and very ingenious devices have been sug- 
 gested for the securing of natural crowns and crowns of porce- 
 lain, amalgam, and gold ; and for this securing^ amalgam has 
 already been extensively and very advantageously employed, 
 and bids fair to almost entirel;^^ supplant every other material. 
 It is probable that large and elaborate " crownings " will be 
 done with gold, for, perhaps, many years yet, but it is not 
 likely that such work will continue to be permitted, much 
 less be demanded, by patients, as the evident practicality of 
 
122 PLASTICS AND PLASTIC FILLING. 
 
 plastics has even now resulted in tlieir being very largely pre- 
 ferred. 
 
 The first use for amalgam in cases requiring entire crowns, 
 is the " building up " of the crown with this material. This is 
 done by one of three methods and by the use of either one, 
 two, or three kinds of alloy. 
 
 If the decay of the crown has progressed so slowly as to per- 
 mit the gradual covering of the pulp by deposition of second- 
 ary dentine, thus leaving a crownless root containing a well- 
 covered vital pulp, the face of the root is prepared with espe- 
 cial regard given to the strength and solidity of the periphery 
 and to the leaving of all living — though softened — dentine 
 over the pulp. Eetaining slots are then made by drilling, with 
 spear-pointed drill, lines of two or more drill-pits at different 
 selected places, and then connecting the pits by using a fissure- 
 drill or small oval burr. These should be filled with an amal- 
 gam made from "contour" alloy — approximate, silver 58, tin 
 37, gold 5 — for its qualities of non-shrinkage, quick-setting, 
 and eminent edge-strength. The fillings should be made a 
 little more than full, and rounded out, that surface for adhesion 
 may be afforded to the tooth-conserving amalgam — made from 
 submarine alloy — with which a base for the crowTi should be 
 built out to the edge, covering the entire face of the root. The 
 crown should then be built on with contour amalgam, which, 
 by alternate layers of plastic mix and wafers, can be carried up, 
 shaped, hardened, and finally finished at one sitting, and which 
 will set sufficiently well in an hour to preclude any liability to 
 accident if guarded with even reasonable care. 
 
 If the crown is upon a bicuspid root, or upon that of a first 
 molar, which shows either during speaking or laughing, the 
 buccal portion of the crown should be cut out as for " facing " 
 — see Technicals — and the concavity be filled with facing 
 amalgam. It will be seen that by this method the varied re- 
 quirements of strong anchorage, excellent root conservation, 
 rapid and strong crown formation, and beauty in presentation 
 are all satisfactorily met, I hav-e made some very serviceable 
 and nice-looking operations of this kind upon cuspid roots. 
 
 If decay has progressed quickly, and a pulp exposure, devital- 
 ization and extirpation has ensued, the operation of crown 
 
■ GENEEAL CONSIDEE ATIONS . 123 
 
 building is much simplified as abundant retention is most 
 readily obtained. In these cases the great advantage of amal- 
 gam becomes apparent in matters of vital importance connected 
 with the duration of possible tooth maintenance, for the two 
 great questions of irritation from dental manipulation, and easy 
 possibility of arranging for relief from probable future trouble 
 are most perfectly solved in the using of this filling material. 
 The canals having been filled with glycerine, into which is 
 passed taper-twisted canal dressings of cotton wool dipped in 
 oil of cloves, these are covered with gutta-percha in such 
 manner as that the floor of the pulp cavity is lined with this 
 and the filling is shaped into a hemisphere. Around this, in 
 undercut grooves, is anchored the amalgam filling, which is 
 then built up into shape and allowed to harden for fifteen or 
 twenty minutes, or until it is enough set to permit of easy 
 cutting without danger of breaking. An entrance is now 
 made, by carefiil, gentle drilling or cutting through the filling 
 into the gutta-percha. This entrance, if upon an articiilating 
 surface, is then almost entirely filled with gutta-percha, over 
 which is placed a covering of amalgam. If it is upon any 
 surface not exposed to attrition, it is, of course, completely 
 filled with gutta-percha. If the relief route is closed with 
 amalgam, it should always be done with " facing " amalgam, 
 as this will leave a distinct demarcation indicative of position 
 of "tap." 
 
 The third method of attaching amalgain crowns is by pins 
 or wire-loop ; for this, either platinum or soft iron wire may 
 be used. I have attached a large number of crowns by each 
 of these two kinds of wire, and I can see no advantage which 
 platinum possesses over iron except that it is more easily bent. 
 I have therefore gradually settled into the habit of using iron 
 wire in cases where the pins were to be left straight and were 
 required to be strong ; and platinum where they were looped 
 or. bent, and were likely to require more accurate bending after 
 being secured in position. 
 
 For either pins or wire-loop, one end should be rivet-headed, 
 and in some cases of straight pins it is requisite that they 
 should be double-headers ; for the making of these I use a 
 slide screw-plate, into the screw-hole of which the pin is 
 
124 PLASTICS AND PLASTIC PILLING. 
 
 placed, and, wlien clamped by the slide, very quickly double- 
 headed with a riveting-hammer. 
 
 Drill-holes, of the size of the rivet-head, having been made, 
 and spheroided with a round or oval burr, the pin or loop is 
 placed in position, and secured with amalgam. This is al- 
 lowed to set, and these then form a firm reliance for the reten- 
 tion of the crown. 
 
 I wish here to speak of the advantage of this method of 
 securing pins over that of screwing them into the dentine. For 
 more than fifty years, the principle of screw attachment has 
 been offered for the purpose of fastening crowns upon roots, 
 but, so far as I have seen, the results show that it is not a 
 desirable method. The efforts during mastication tend to 
 produce an imperceptible loosening, which, trifling as it is, 
 increases quite rapidly after being once established. Soon 
 the motion becomes observable, and then, almost immediately, 
 the screw-thread, acting as a file, cuts the pin loose, and the 
 crown drops off. 
 
 Just the opposite result will ensue from the rivet-head and 
 filling securing, for these have been proven to hold until the 
 wire has been broken, or wrenched out by fracture of the root, 
 or undermined by the progress of recurring decay. 
 
 The second use for amalgam, in cases requiring entire crowns, 
 is for the purpose of attaching gold crowns. These are made 
 by bending a ribbon of pure gold, cut from plate made of gold- 
 foil scraps or old gold fillings, and soldering it as a ring with 
 an approximate fit for the face of the root to be crowned. The 
 anchorage is then obtained, and a filling of submarine alloy is 
 made which extends a short distance out from the gum. When 
 this is a little hardened, the gold crown is pressed into position, 
 cutting through the amalgam, and thus forming a joint at the 
 neck of the root, not by slipping over it and banding it, but 
 by resting upon it, which joint is then made perfect by tapping 
 the still workable amalgam accurately into apposition with the 
 upper edge of the encircling ring of gold. Contour amalgam 
 is now employed for filling the entire crown, and thus it is 
 secured upon the root. One might naturally suppose that the 
 mercury from the amalgam would permeate and discolor the 
 ^old, but it does not do this, and, from this fact, enables us 
 
GENERAL CONSIDERATIONS. 125 
 
 to utilize this facile and durable method of fastening such 
 crowns. This style of work formed my " intermediate " be- 
 tween the gold crowns which I formerly made with foil and 
 the amalgam or amalgam and porcelain crowns which I now 
 use almost exclusively. 
 
 The third use for amalgam, in cases requiring entire crowns, 
 is for the replacing of natural crowns which have been broken 
 off. This is sometimes a very gratifying operation, both to 
 patient and practitioner, for it is usually alike pleasing and 
 unexpected to the patient to have such restoration made, and 
 it produces a result which, for perfection of appearance, cannot 
 be equalled by any other process. 
 
 The crown, possessing as it does all the special peculiarities 
 which pertain to that individual location, if replaced, gives to 
 the work a harmony with surroundings whtch cannot be other- 
 wise attained ; and it is for this reason that it is not only war- 
 rantable, but eminently desirable that the attempt should be 
 made, especially for lady patients, and especially again for the 
 conservation of facial identity or great personal beauty. 
 
 For this purpose the crown should be so drilled as to obtain 
 the necessary mechanical hold for its part of the securing 
 filling. The root should be drilled out deeply, and bell- 
 shaped at the entrance, so as to give broad,- gtrong retaining 
 surface for the amalgam at the union between crown and root. 
 The lahial portion of the crown — it is supposed that this op- 
 eration would not be deemed advisable for any tooth posterior 
 to a cuspid — should be lined either with a very thin lining of 
 oxy-chloride of zinc — in which there is little or no strengxu — 
 or a somewhat thicker lining of facing amalgam, which may 
 subserve the purpose of increasing the strength of attachment ; 
 the object of which is the prevention of discoloration, for 
 neither are strong enough to rely upon for support. 
 
 The root should now be nearly filled, and the tooth having 
 been placed accurately in position, and being held either by 
 the finger and thumb, or retained positively by gutta-percha, 
 plaster of Paris, oxy-cbloride of zinc, or zinc-phosphate sup- 
 ports, mesially, labially, and distally, should now be secured by 
 contour amalgam. This should be allowed to set for at least 
 an hour, when the supports may be carefully removed. Such 
 
126 PLASTICS AND PLASTIC FILLING. 
 
 teeth sliould not be bitten upon for a day or two, if it is possible 
 to avoid it, for it is very essential to success that the amalgam 
 sliould be tlioroughly set before it is subjected to tbe slightest 
 strain. For increased strength, a small platinum-pin may be 
 secured in the root and permitted to pass into or through the 
 crown, as in a Bonwill pivot. 
 
 The fourth use for amalgam in these cases is for the securing 
 of natural or porcelain crowns which have been fitted to crown- 
 less roots. From what has been said relative to the replacing 
 of crowns which have been broken off, it will require but few 
 words to present this modification of that operation ; but it 
 will be seen, upon slight presentation, that modifying considera- 
 tions do exist. A crown which had been broken off would, 
 under almost all ordinary circumstances, have been subject to 
 extensive decay prior to fracture ; while a selected crown — 
 either natural or porcelain — would be perfect in contour. The 
 one, the porcelain, would be so drilled and prepared internally, 
 and at its neck, as to require but trifling adaptation by grind- 
 ing, and subsequent securing by contour amalgam ; the other, 
 the natural, would require drilling and internal shaping of 
 cavity to correspond with the prepared cavity of an artificial 
 tooth ; and it should then be " lined " to prevent discoloration. 
 
 Pivoting Teeth»^ — In this work, as in the whole line of opera- 
 tive dentistry, amalgam has wrought most radical changes ; it 
 seems to have supplanted the entire range of round and square 
 box- work with split-pin — gold — pivots; it has largely taken 
 the place of foil for securing these tubes and boxes, even if they 
 are used. It has only gutta-percha as a rival for the securing 
 of metallic-pin pivots ; and it welcomes the aid of gutta-percha, 
 for it recognizes in it a most notable plastic. It has essentially 
 modified every phase of pivoting, and has rendered that opera- 
 tion, which was formerly either disgusting — wooden pin in 
 plain root — or very tedious, painful, and expensive — back- 
 stayed-plate tooth built in with gold foil — a painless, compara- 
 tively inexpensive, and cleanly piece of work ; equally beauti- 
 ful in appearance ; equally durable, and requiring but an hour 
 or two for its doing. 
 
 Its first great change was the supplanting of the increase of 
 size of wooden pivots, as the roots became more and more de- 
 
GENERAL, CONSIDERATIONS. 127 
 
 cayed, by the filling of tlie enlarged pivot-liole witli amalgam, 
 and the drilling of such sized hole as permitted a return to the 
 original size of wooden pin. This was a great step in advance, 
 as by it many a root was saved for many a year of usefulness, 
 and even retained until further modifications resulted in the re- 
 pivoting of teeth, in a superior manner, upon roots which had 
 already supported pivot teeth for more than a dozen years, and 
 for which fears as to their possible long continuance had been 
 entertained many years before, as pin after pin had been in- 
 troduced with biennial regularity. 
 
 The day of wooden pins is slowly passing away, and yet this 
 use of amalgam will probably continue for a long time to come, 
 and will be resorted to, as it now is, for foundations for first 
 wooden-pin pivotings instead of permitting the roots to become 
 almost ruined before lining them. 
 
 But the marked influence of amalgam over pivoting is most 
 strikingly exemplified in the operations as variously proposed 
 by Dr. Bon will, Dr. Gates, and myself. 
 
 Bonioill Pivot. — Select pivot-tooth, — Bonwill's ; prepare 
 root, and fit crown ; fill root with " usual " amalgam — soft 
 make — and force entrance for platinum-pin in amalgam with 
 a pointed instrument. Grasp pin — which should be of right 
 length, tri-flattened, and barbed — with forceps, and press it 
 forcibly home. Tamp amalgam, to be sure that it well secures 
 pin. This pin may equally well be rivet-headed and filled into 
 the root. Eeplace crown to see that it fits. It is advantageous 
 to bend pin so that it rests against palatal side of hole in crown, 
 as thus the crown is retained nicely in place. Fill base of 
 crown through to palatal side with amalgam — plastic — and 
 with one finger over palatal hole press firmly into position by 
 twisting, and afterwards tapping, by wooden pin, with mallet. 
 The fingers will be best if the amalgam is not too stiff; then 
 " wafer " to harden the amalgam. After it is thoroughly hard, 
 smooth off the exposed portion of filling and the end of the 
 platinum-pin if protruding. 
 
 I have set quite a number of these " pivots," and have reason 
 to be well satisfied with the firmness, cleanliness, and appear- 
 ance of the results, and with the reasonable facility with which 
 the operation is performed. 
 
128 PLASTICS AND PLASTIC FILLING. 
 
 Altliougli it is possible to make a Bonwill Pivot operation 
 witli almost any plastic-filling material, it is jet deemed prefer- 
 able by the inventor that it be done Avitli amalgam, and with this 
 belief Dr. Bonwill has devised a pin of peculiar shape made from 
 a " Combination Metal," to which he states the amalgam unites 
 tightly, and which he claims adds greatly to the strength and 
 value of the work. 
 
 For an accurate description of the Bonwill operation, and for 
 its complete illustration, reference can be made to the "Cosmos" 
 for August, 1880, p. 410, and for June, 1882, p. 304. 
 
 The Gates Pivot. — Such radical changes have been made in 
 this " pivot," and such ingenious instruments have been devised 
 for the accurate performance of the work, that I deem it better 
 to refer my readers, for full information in regard to this opera- 
 tion, to the very explicit and admirably illustrated article in 
 the "Cosmos "for March, 1882, p. 119. 
 
 Flatjr/s Ring Pivot. — This method of pivoting is so easily 
 employed in all ordinary cases, and is capable of adaptation in 
 so many difficult cases, that I have thought it advisable to de- 
 scribe it. Select ordinary plate-tooth ; fit it to root, and bevel 
 cervical portion -of tooth as in "Flagg Pivot. " Make small ring, 
 of platinum wire, for straight-pin tooth, or semicircle for cross-pin 
 tooth, and solder it to the pins above or below, as indicated — 
 cross-pin tooth preferable. Take occlusion and cut oft' pin as 
 required. Fill platinum pin in root.* Place tooth in position 
 and bend ring, which should be of sufficient size to touch lingual 
 edge of root, letting the ring slip over the pin. Secure tooth, 
 with "adhesive wax," to adjoining teeth, and fill around pin and 
 ring with Contour Amalgam, — soft make. The advantages of 
 this method are found to consist in the almost limitless variety 
 from which to select tooth ; the latitude, which the ring allows, 
 for placing the tooth in any desired relation with the root 
 or with adjoining teeth, and the ease with which apparently in- 
 surmountable difficulties are overcome. It is usually advisable 
 to allow the adhesive wax to remain, for a day or so, until com- 
 plete hardness of amalgam is attained. For this purpose the 
 amalgam should " set " for an hour, and the wax be then 
 melted and smoothed into contour with the adjoining teeth by 
 instrument No. 7, quite hot, as by this means a firm and neat 
 * For roots which may require " venting " use platinum tube for pin. 
 
GENERAL CONSIDERATIONS. 129 
 
 adhesion of wax is effected, and good temporary support ob- 
 tained. 
 
 In cases of close occlusion, where strength, of crown is im^ 
 paired by necessary removal of material, I have found the " ring 
 pivot" easy of adaptation and very strong. 
 
 Flagg Pivot. — Select plate-tooth, fit it to root, and bevel it 
 from near the pin — cervical — or pins, if cross-pins, to the 
 labio-cervical edge. Solder a platinum-pin to it as a backstay 
 and pivot combined, leaving it rough or grooved on both sides 
 of pin for a retaining hold to the finishing palatal amalgam. 
 
 Fill the root, which is treated, prepared for strong mainte- 
 nance of filling, and " bell-muzzled," or " open-mouthed," with 
 a good usual or contour alloy — quick-setter; non-shrinker ; 
 good edge-strength. I prefer to give this a day to harden 
 thoroughly, but in case of need it may, with care, be worked 
 in an hour or two. 
 
 Into the root-filling, drill a hole rather larger than the plat- 
 inum-pin, as near to the palatal portion of the filling as possi- 
 ble, and directed, slantwise, to the apical centre of root-filling ; 
 then "fissure-drill" the hole towards the labial portion of the 
 filling, trying the tooth until it sets just right, with the pivot- 
 pin pressing hard against the labial side of the now oval pivot- 
 hole. By this method the tooth is accurately placed in position^ 
 and easily held firmly in place^ while the pin is secured hy filling 
 the pivot-hole with amalgam. 
 
 Let this harden for half an hour, and then add amalgam, in 
 contour, to the root-filling and palatal face of the porcelain 
 tooth. It is at this point of the operation that the need for 
 " bevelling " the cervical portion of the tooth is demonstrated ; 
 for, by this bevel, one is enabled to make, by filling, a perfectly 
 tight joint at the labio-cervical junction of tooth with root, 
 and also to secure a strength of amalgam equal to the entire 
 surface of root-filling. 
 
 This makes a strong, cleanly, and satisfactory operation, 
 
 ^^ Guarding'''' or repairing gold fillings^ and refilling cavities^ 
 from which gold fillings have been lost, in teeth which still con- 
 tain gold fillings. 
 
 We have now reached a singularly vexed question in den- 
 tistry, viz,, the use of two metals in one tooth, or, possibly 
 9 
 
130 PLASTICS AND PLASTIC FILLING. 
 
 more dubious, the use of two metals in one cavity. In the 
 discussion of this question, I shall regard amalgams as metallic 
 compounds, each of which is possessed of that definite poten- 
 tial, conductivity, resistance to tarnish, etc., which makes of it, 
 practically^ a metal, and thus renders fillings of tin and gold^ 
 and amalgam and gold, equally Sz-metallic, dentally. There is 
 scarcely any point which has been more frequently spoken to 
 in discussion than this, and probably no one upon which more 
 theory and less practice has been expended in antagonism. 
 
 From the fact, which has been alluded to, that galvanic ac- 
 tion can be excited by fillings of different metals in close prox- 
 imity, and is variously demonstrated by metallic taste, pain, 
 shock, and even spark, it has been largely concluded that the 
 placing of such must necessarily be detrimental. 
 
 Eeference to discussions upon this point will show that 
 while only vague ideas of how this combination could work 
 injury were enunciated, positive belief that it would do so was 
 unhesitatingly and forcibly expressed ; and this, too, Strangely 
 enough, vfithout any distinction as to relative placing of metal; 
 whether equally or unequally exposed, or even whether both 
 were exposed or one completely covered. 
 
 To such extent is this peculiar discussion carried that the 
 same gentlemen are found inveighing most decidedly against 
 the partial filling of ordinary cavities of decay with tin, and 
 the covering of this metal with gold, upon the ground that 
 the union -of two metals in one cavity would produce pulpitis, 
 death of the pulp, and eventually alveolar abscess, and, at 
 other times, are equally strong in their advocacy of the em- 
 ployment of sheet-lead as a pulp-protector (!) in cavities con- 
 taining almost exposed pulps, and the filling over it with gold. 
 This appears to have been done with the idea that lead was not 
 a metal ! 
 
 Views upon this " two-metal question " have become modi- 
 fied by time and observation, until it was very recently an- 
 nounced — " Cosmos," Nov., 1879, p. 626 — that observation had 
 shown " that amalgam and gold may he used in the same tooth, 
 and in immediate contact^ with no unfavorable results, notwith- 
 standing the theories which have obtained to the contrary" — 
 the italics are mine ; while to a question regarding the conse- ■ 
 
GENERAL CONSIDERATIONS. 131 
 
 quences of filling two proximate cavities respectively with, 
 gold and amalgam, contact being permitted, the same speaker 
 replied that he would " not have allowed them to touchy 
 
 The deduction is that it might be that no unfavorable conse- 
 quences would ensue, even though the metals were in contact; 
 but that contact should be avoided, if possible. 
 
 During the same discussion, reference is made to my claim 
 that " the relation of the two is the salvation of the tooth," 
 which I do claim most decidedly. 
 
 I would suggest especial reading of the remarks of Dr. Bon- 
 will, — same discussion, page 631, — for it is very well known 
 that this gentleman is one of the most thoroughly informed 
 electricians of the dental profession. 
 
 His view is, that when gold touches amalgam in proximate 
 teeth, the teeth should be so pressed apart and the fillings so 
 contoured as that " when they come together again no ordinary 
 attrition will cause them to separated With this I agree. 
 
 It is now eighteen years since my attention was directed to 
 the systematic investigation of this subject. I was led to this 
 by the placing under my charge of a tooth — right lower wis- 
 dom — which had a large cavity upon the articulating face, 
 that had been filled for nearly twenty years with gold, and an- 
 other upon the buccal face, which had been filled three times 
 during the same period with the same material. The patient 
 was then fifty -nine years of age. I suggested the trial of amal- 
 gam in the cavity from which the gold had so frequently failed, 
 and the suggestion was accepted, 
 
 A few days after the operation, the patient returned with the 
 statement that a metallic taste was frequently perceptible, and 
 that occasionally 'during mastication a painful shock had been 
 felt in the filled tooth. 
 
 Upon examination and experimentation, I found that during 
 laughing the cheek so pressed upon the two fillings as to make 
 and retain gentle connection between them, giving rise to metal- 
 lic taste ; and that during the mastication of a piece of cracker 
 an occasional sudden and forcible connection would be made 
 which caused a shock. 
 
 It occurred to me to connect the fillings as the first means of 
 preventing shock ; and I informed the patient that if metallic 
 
132 PLASTICS AND PLASTIC FILLING. 
 
 taste supervened, it would pass away witt. the discoloration of 
 the amalgam filling. This connection was made by cutting 
 through the small intervening portion of enamel, — both the 
 cavities were large, — and the sequence proved the correctness 
 of the prognosis ^ there were no more shocks, and the metallic 
 taste became less each day until it ceased altogether. 
 
 But another result in due time attracted my notice. The 
 gold filling upon the articulating face was slightly defective, 
 sufficiently so for me to request an occasional opportunity for 
 its examination. Year after year passed, and seventeen years 
 after — patient aged seventy-six — I removed this tooth with 
 my fingers, it having loosened from combined excessive use 
 and gum and process recession, with the amalgam filling cred- 
 ited with its seventeen years of service, and with the gold fill- 
 ing no more defective than it was seventeen years hefore. 
 
 It was as the sequence of watching this filling and others 
 resultant from this experiment for five years, that twelve years 
 previous to this extraction I had ventured upon the statement 
 to the class of the Philadelphia Dental College that I thought 
 it probable that " the relations of metals in bi-metallic fillings 
 gave to such fillings therapeutic value, and that this value was 
 dependent upon the cont&ct of the metals and the exposure of both 
 metals to the fluids of the mouth. 
 
 It was this belief which led me to " guard " with crescents 
 of tin the cervical walls of cavities which I proposed filling 
 with gold. It was this which led me to fill the crevices around 
 failing gold fillings, especially at those "vulnerable spots" 
 which were inaccessible, and under gums, with amalgam. It 
 was this which m<ade me feel warranted in saying at the "New 
 Departure" meeting, of the New York Odontological, Nov. 1877, 
 that I had, "up to April, 1877, 1053 gold fillings of my own, and 
 many other operators'^ doing service only because they had been 
 guarded in this way" by tin, gutta-percha, or amalgam. 
 
 Believing that the injury to soft dentine which would arise 
 from contact between it and gold by difterence of potential 
 would be notably counterbalan'ced by contact again between 
 gold and amalgam, I can readily see that, as has been stated by 
 Dr. Dixon, amalgam fillings might be serviceably guarded by 
 gold; while, upon the same principle, gold filliiags would be 
 
GENERAL, CONSIDERATIONS. 133 
 
 guarded by amalgam, as instanced bj Dr. Daniel Neall; but 
 upon principle I should expect in a very soft tootli, one that 
 markedly needed help, that a gold filling circumscribed by amal- 
 gam would do longer service than an amalgam filling circum- 
 scribed by gold. 
 
 But it is not alone for the simple maintenance of integrity in 
 any one or more fillings, that I would advocate the making of 
 bi-metallic fillings or the modifying of fillings already made of 
 one material so as to make of them "bi-metallic;" for my expe- 
 rience in great numbers of mouths points to the conclusion that 
 such fillings may be definitely relied upon for the making of 
 such change in the oral fluids as will be protective of other 
 fillings, preventive in some degree of caries, curative of sensi- 
 tiveness of dentine, and even beneficial to general health. 
 
 It is with much deliberation that I have come to these con- 
 clusions ; and yet it is not without some hesitancy that I have 
 spoken of them from the lecture-stand, and now present them 
 for professional consideration. The instances in which the 
 making of six or eight such fillings in mouths where failure 
 of fillings was a constantly recurring thing, and where exquis- 
 ite sensitiveness of dentine was the unfortunate concomitant, 
 and where such failures became from that time notably less, 
 and markedly in connection with the gold fillings, and where 
 the sensitiveness of dentine was modified even to almost com- 
 plete normality, are so numerous in my practice that I could 
 not overlook them even if I would. Indeed, these results have 
 been so notable, that in many mouths containing partial den- 
 tures upon gold plates, I have supplemented my efforts at pre- 
 serving the remaining teeth with plastic fillings by breaking a 
 tooth or block from the artificial work, and building in its place 
 a tooth or block of amalgam. 
 
 The change, both local and systemic, which so soon occurs, 
 is too frequent and too decided for me to doubt that the post 
 hoc is a propter hoc. 
 
 Fractures of tooth from- fillings, either of gold or amalgam. — 
 With the classes of teeth which .require large fillings, it is no 
 unusual thing to find cavity walls of paper-like thinness, or 
 portions of tooth possessing considerable thickness, but at- 
 tached to the roots by narrow connections. In such cases a 
 
134: PLASTICS AND PLASTIC FILLING. 
 
 violent contact with unyielding material, sncli as crackers, 
 candies of certain kinds, pieces of bone, or oyster-shells, etc., 
 will inevitably crush or break off such fragile or insecure 
 structure. 
 
 These accidents are probably most frequent with bicuspids, 
 especially those of the upper jaw. This is due to the tnarked 
 predisposition of these teeth to decay largely, and in such man- 
 ner,, mesially, distally, and in the articulating face, as to afford, 
 after filling, the least remaining strength for resisting the dis- 
 advantageous wedging of food between the buccal and palatal 
 cusps. 
 
 It is to avoid this contingency that Prof. D. D. Smith has 
 suggested the advisability of excising the palatal cusps, and, 
 in very rare cases, even both cusps, of such frail teeth, and 
 either restoring contour with filling material, or so filling the 
 teeth as to make of them thickened cuspids. This operation 
 will be recognized as founded upon correct principle, and is 
 rendered peculiarly feasible by the use of plastics, in which, 
 although " combination " fillings are almost universally indi- 
 cated, amalgam nevertheless performs the most important part. 
 
 It will be noted that such teeth are completely "slotted" 
 through ; the remaining walls are necessarily thin, and it is 
 important that a good color should be maintained, at least, 
 buccally. For this purpose the buccal wall is lined with oxy- 
 chloride of zinc, and the buccal cusp is so undercut as to afford 
 the strongest possible hold for the strongest kind of amalgam, — 
 contour, — with which the tooth is filled after having secured the 
 cervical portion of the cavity by a thin layer of " submarine." 
 If it has been deemed desirable to cut off the buccal cusp, in 
 consequence of exceeding frailty at the bucco-cervical line, it 
 will be necessary to finish by the use of facing amalgam. 
 
 But it is in the repairing of ordinai-y fractures of tooth sub- 
 stance from fillings of gold or amalgam, that amalgam most 
 positively demonstrates its extraordinary capabilities ; for, in 
 such cases, froin the least to the greatest^ the reparations are 
 made with almost equal facility. 
 
 Every indication is met, no matter how diversified, no m.at- 
 ter how numerous, no matter how imperative ! If a mere 
 "shell" has been "artistically" filled with gold, and a long 
 
■ GENERAL CONSIDERATIONS. 135 
 
 sliver of enamel lias been broken out from the disto-palatal 
 wall, a more difficult or annoying piece of repair, with gold, 
 could not well be imagined, and yet, with soft-mixed " usual '' 
 amalgam, a repair can- be made by " cold-soldering" — see Tech- 
 nicals — which will be so serviceable as to probably be in good 
 order as long as any other portion of the filling, and it can be 
 done with perfect facility, with comfort to the patient, and in 
 ten or fifteen minutes. 
 
 If a large, strong molar has been handsomely and perma-. 
 nently — accidents aside — filled with gold, and, as the result 
 of a tremendous bite, the whole buccal face of the tooth has been 
 fractured off, a repair of gold would be far more tedious, far 
 more difficult, and far more expensive than was the original 
 filling. With contour amalgam, this repair would be, com- 
 paratively, but a trifle. It would take no more time than 
 would an ordinary filling ; it would be done without physical 
 tax to either operator or patient, and would be far less expen- 
 sive than was the filling to which it would be built on. 
 
 If small pieces of tooth are fractured, an opportunity for 
 making, of the remaining filling, a bi-metallic, is offered. This 
 is done so nicely, with such celerity, and with so little cost, as 
 to most favorably impress patients with the working of plastic 
 dentistry^ and thus, by " little things," prepare them for continu- 
 ances of relief from infliction, until they are shown that the 
 resources are almost endless, and until they know, " of their 
 own knowing," that good, substantial, compensating dentistry 
 is not necessarily attended with the non-compensating inflic- 
 tions to which they had been, for years, subjected. 
 
 Split Teeth. — For more than thirty years, attempts have been 
 successfully made at rendering teeth, which had been split 
 through the roots, useful by " bolting." The making of the 
 gold bolt with its screw and burr ; the countersinking and 
 covering of the screw-head by filling ; the after preparation 
 and the final filling of the split root and tooth with gold, con- 
 stituted a series of manipulations which made the operation 
 difficult, delicate, and very expensive. All this is changed, 
 and, although the work as now done with amalgam could be 
 done with gold, and beautifully done, and could not be done 
 nearly so well with the amalgams almost universally employed, 
 
136 PLASTICS AND PLASTIC FILLING. 
 
 it can yet be letter done, taking everytliing into consideration, 
 by tbe " amalgam metkod " of the present day than by any 
 other way. 
 
 If the split tooth contains a vital pulp, the devitalization of 
 this is the first thing to be done. The parts are gently drawn 
 into apposition by means of book-binder's thread passed around 
 the neck of the tooth, and an application is carefully punctured 
 into the pulp. This application should be very small in quan- 
 tity and should be largely acetate of morphia paste. 
 
 If possible, it should be only this, and especially for the bul- 
 bous portion of the pulp, and if the arsenical application is 
 found necessary, it should be made as intimately mixed with 
 cotton wool as possible, instead of being introduced loosely in 
 paste form. The " devitalizing fibre " is admirably adapted 
 for this purpose, to be used in very minute pieces. It must be 
 remembered that the split is a direct route to the peridentium, 
 and that the least arsenical impress upon that membrane at so 
 high a point will probably eventuate in death of the tooth, and 
 will be naturally followed by exfoliation. 
 
 The pulp having been devitalized, the tooth is placed in the 
 same category with all split pulpless teeth, for which the first 
 indication is the accurate joining together of the parts. This 
 is accomplished by ligating at the neck with book-binder's 
 thread, drawing it as firmly as is consistent with comfort, and 
 having the knot held by pressure from a suitably shaped ser- 
 rated plugger, until it is securely tied. The thread should then 
 be allowed to shrink from moisture, and in ten or fifteen minutes 
 a second ligature should be tied as firmly as possible either 
 above or below the first ligature. The position of the second 
 ligature is decided by the manner in which the parts draw to- 
 gether. The second ligature should then be allowed to shrink, 
 when a third ligature should replace the first one, or be passed 
 around the tooth on the opposite side of it from the second one. 
 
 The objects which must be gained by the ligation are, first, 
 the accurate placing of the parts in apposition, and, second, the 
 firm maintenance of this condition. The tooth is then care- 
 fully entered by drilling ; the pulp cavity is cleansed, and the 
 canals — enlarged by Talbot reamers — are, if possible, utilized 
 for effecting the reparation. In first bicuspids and upper and 
 
GENERAL CONSIDERATIONS. 137 
 
 lower molars, tliese are generally available, but in single rooted 
 teeth, tlie uniting drillings have to be made according to cir- 
 cumstances. The principle of securing is by " dumb-bell " or 
 "double-headed" union; a drill-hole is made in each portion 
 of split root, or the canals are enlarged in bi-rooted or multi- 
 rooted teeth ; these large, round drill-holes are then united by 
 narrow fissure-drilled canals. The cracks of fracture are 
 opened from the pulp-cavity almost to the periphery, and then 
 the drill-holes, fissured canals, and cracks of fracture are all 
 filled with contour arnalgam. It is sometimes possible to add 
 dove-tails cut in the crown portions of the teeth, but, if this is 
 not practicable, drill-pits should be made in the substance of 
 each part, and these should be enlarged into spheroids, that 
 thus increased strength- of union be given to this part of the 
 filling. If there is not substance sufficient for this in conse- 
 quence of previous extended decay, drill-holes should be made 
 completely throuyh the enamel ; these should be countersunk 
 upon the enamel surface, and thus " rivet-head " fillings be 
 made. 
 
 From what has already been said, it will be at once suggested 
 that crown-linings and rivet-heads exposed to view should be 
 made of facing amalgam, while all the other filling should be 
 of contour amalgam. 
 
 I have quite a number of these operations in hard service, 
 many of which have been doing duty for from one to nearly 
 five years, and, as a rule, they have thus far been more satis- 
 factory than the "bolted" operations, though, some of these 
 have done remarkably well ; but the decided advantages of the' 
 amalgam "joining" are the greater facility with which the 
 work is done ; the almost complete avoidance of irritation dur- 
 ing dental manipulation, and the reduction of expense to one- 
 half, and in large cases to one-quarter that of the " gold bolt " 
 operation ; while the compensation for time of operator is 
 equally great and the comfort and satisfaction to the patient are 
 increased. 
 
 The ligatures should remain on the tooth for a day or two, if 
 there is no gum irritation from them ; but if that one nearest 
 tlie gum irritates, it should be removed upon completion of 
 <)peration. In a couple of days the ligatures should be cut off, 
 
138 PLASTICS AND PLASTIC FILLING. 
 
 and any finishing whicli may be required in parts covered "by 
 them, should be looked for and done. 
 
 Perforated Teeth. — These are "teeth in which decay has so 
 progressed, or in which drilling or excavating has been carried 
 so far, as to have made an opening through the cementum ; they 
 are frequently regarded as not amenable to treatment, or, if 
 attempted, are usually considered as extraordinary in the line 
 of dental manipulation. A trial of some such cases, with plas- 
 tic fillings, will soon make of them, to all practitioners, that 
 which they are to the plastic workers, viz., matters of very little 
 moment. Cotton wool, saturated with oil of cloves, is pressed 
 gently into the cavity, and allowed to impinge upon. outside 
 tissue just sufficiently to permit an accurate contour healing — 
 neither concave nor convex. The cavity being then very gently 
 dried with absorlent cotton^ a smooth piece of low-heat gutta- 
 percha — white — is laid over the orifice and secured in position 
 by accurate pressure — oiled instruments, cold — against the 
 edges. This is then firmly fixed by submarine amalgam — soft 
 niix — with which all the floor of the cavity is covered. This 
 removes all "perforation" complication, and reduces the work 
 to ordinary, with the exception of regard for possible future 
 contingencies. If the perforation is very large, the tooth in 
 the lower jaw, and the patient of strumous or otherwise doubt- 
 ful^diathesis, all arrangements for occasional vent, if required, 
 should be made, though my experience is, that the "extraor- 
 dinary" concomitants of these cases are the ease with which 
 they are generally treated, and the equanimity with which the 
 surrounding tissues accept the conditions. 
 
 Loose and divided Boots. — We have now arrived at what may 
 be regarded as the great dividing line between gold and plastic 
 dentistry. 
 
 Up to this point, the gold-worker is able to do, after a fash- 
 ion; all that can be so effectually accomplished, so much more 
 easily, with plastics; but now the limit has been reached. We 
 here enter upon a broad field of impossibilities to the gold- 
 worker, and yet a field in which the marvels of plastics seem 
 fairly to revel," 
 
 A patient applies, who, having lost nearly all the teeth, has 
 worn a partial denture clasped to bicuspids. One of these has 
 
- GENERAL CONSIDERATIONS. 1S9 
 
 gr9,diially loosened, and has finally dropped out. The roots of 
 an adjoining molar, quite loose and decidedly doubtful, tlie 
 palatal separated from the buccal, are each drilled out, and 
 " ring-bolts " of platinum wire — made by rivet-heading one 
 end, and forming, by round-jawed pliers, a ring upon the 
 other end — are filled into them. These fillings having set, 
 the roots are drawn together by a ligature passed through the 
 rings. When they are fairly in apposition, a foundation of 
 submarine amalgam is made, resting upon the rootSj and held 
 between the bolts. This is allowed to set thoroughly, when 
 contour amalgam is built up domelike to the ligature, entering 
 into the rings and securely binding the whole together. After 
 this has hardened, the ligature is cut off, a clasp is approxi- 
 mately adjusted and soldered on to the work ; a bicuspid is 
 also added, and the piece is placed in position ; then, with 
 contour amalgam, a nice crown is readily built on, fitting the 
 clasp to perfection, from the cervical edge of the previous 
 dome-like building down to the now entirely covered tops 
 of the ring-bolts. 
 
 This soon sets, the work is carefully removed, any defect of 
 filling is made perfect by additions of amalgam, and the crown 
 is smoothly finished ofi". In an hour this can be used with 
 safety, and, as the result of such work, the patient is made 
 " more comfortable than ever before." So he said. 
 
 A patient applies who has but two teeth left on either .side 
 for mastication ; one of these, a lower molar, has recently been 
 broken, and, in the fracture, the distal half of the crown, 
 with a large and very expensive filling, has been broken off, 
 and the distal root split apart from the remaining crown and 
 root. In a few days the separation between the roots became 
 enlarged from the forcing of food during attempts at mastica- 
 tion upon the half-crown, and such soreness supervened as to 
 preclude further effort upon that side. The other side has 
 given such decided evidence of trouble, from its constant use 
 for a week, that relief is sought. A ring-bolt is- filled into the 
 distal root ; the canals of the mesial root are widely opened 
 for retaining hold; and, a large drill-hole having been made 
 through the mesial face of the half-crown, it is well counter- 
 sunk from the outside. The distal root is drawn back into 
 
140 PLASTICS AND PLASTIC FILLING. 
 
 position hj a ligature passed tlirough the drill-liole and around 
 tlie bolt. A foundation is made of submarine which, connects 
 the bolted root with the mesial half, held by the canal hold ; 
 when this is hardened, the ligature is taken oif and a contour 
 crown is built on, around, and through the ring-bolt and through 
 the mesial drill-hole, and is rivet-headed in the countersink. 
 
 This has been eaten on, most satisfactorily, for several years. 
 
 A patient applies, seventy years of age, who has lost nearly all 
 teeth except the superior and inferior incisors and cuspids, and 
 these are worn almost to the gum. The left lower second molar 
 has advanced quite to the position formerly occupied by the 
 first molar. A crown has just been lost from the upper jaw, 
 which, though rather loose, has subserved the purposes of mas- 
 tication " much better than nothing." It is shown, and is found 
 to be the. crown of the upper second molar which had decayed 
 from the palatal and mesio-buccal roots, which had gradually 
 loosened and come away. Another root, the disto-buccal of the 
 first molar, is in position. These three distinct and separated 
 roots of two teeth are drawn together and utilized by crowning, 
 and the patient is " glad the old tooth came out ; " for he eats 
 " so much better with the new one." 
 
 A patient applies whose eating has been done, for a number 
 of years, by two molars of the right side and by two first bi- 
 cuspids of the left side. There are no other teeth or roots 
 on the right side ; bat there is the second superior bicuspid of 
 the left side, the root of the second inferior bicuspid — loose, 
 — and a lower molar root, quite near to it and quite firmly 
 implanted. 
 
 The crown has recently been broken from the first inferior 
 bicuspid, and, the eating having necessarily been done exclu- 
 sively upon the right side, the two molars have begun to com- 
 plain. The three roots are ring-bolted, and a long, continuous 
 crown is built upon the three. The two firm roots hold the 
 middle loose one strongly in place, and both the bicuspids of the 
 left superior jaw are utilized. Ample masticating surface is 
 thus given, and the patient relieved from the burden of arti- 
 ficial work. 
 
 I. is needless to multiply cases, for tnese will suffice to dem- 
 onstrate how it is that the plastic-worker can take the wrecks 
 
GUTTA-PERCHA. 141 
 
 alike from gold-work and from neglect, and make tlie patients 
 " rejoice and be glad " at a time of life when they have come 
 to realize the impossibility of enduring further infliction, the 
 folly of continuing needless neglect, and the almost boundless 
 signification of the phrase, " comfort from plastics J^ 
 
 AETICLE XIII. 
 G UTTA-PEB CHA. 
 
 THIS material was offered for dental consideration about 
 thirty years ago. 
 
 It was suggested as a temporary stopping for frail teeth, and 
 was recommended for its ease of manipulation ; its non-irrita- 
 ting and non-conducting qualities ; its insolubility in the fluids 
 of the mouth, and its reasonable resistance to attrition. 
 
 These desirable characteristics caused it to find favor in a 
 limited degree, even though its color — a dark brown — was 
 very objectionable ; but, upon the introduction of a mixture 
 known as " Hill's Stopping," and supposed to be composed of 
 gutta-percha, quicklime, and pulverized silex (a supposition 
 probably entirely erroneous), it was quite promptly accepted 
 with marked favor, and soon took position as a very valuable 
 adjunct in practice. 
 
 Its inventor, Dr. Hill, had quite exalted ideas of the value 
 of his invention, for he stated that while he did " not expect it 
 to supersede gold entirely," he nevertheless believed that it 
 could be " advantageously substituted for that material in many 
 instances." 
 
 The advocates of the " compatibility theory " believe, at the 
 present day, that his views were correct, and that if they had 
 been very much more universally accepted, the result would 
 have been a vastly better record in the saving of teeth. 
 
 Other compounds, of a like nature, were soon introduced as 
 "superior," but with little or no just claims to such distinction, 
 as, after trying a great variety of ingredients for the purpose 
 of whitening the gutta-percha without seriously impairing its 
 toughness, nearly all the better grades were, and are, composed 
 mainly of gutta-percha and oxide of zinc. 
 
142 PLASTICS AND PLASTIC FILLING. 
 
 Lik.e otker manufactured articles, it was soon found that 
 much more depended upon the art of manufacture than upon the 
 components of the filling material^ and at present the relative 
 quality of the various " makes " is due largely to this. 
 
 Early in the use of gutta-percha stoppings it was noticed 
 that "remarkable results" were being attained, and those who 
 were investigating these with a view to the future modification 
 of practice came in due time to regard them with exceeding 
 favor. 
 
 It was gradually accepted that gutta-percha had its place not 
 only as a " temporary filling," but as a stopping of extraordinary 
 permanency, having but two demerits of note, viz. : inability to 
 resist the attrition of mastication, and a degree of shrinkage 
 which permitted leakage and a consequent " clouding " of the 
 filled tooth. 
 
 The first of these objections was only to be overcome — in the 
 use of the one material — by restricting its employment to such 
 cavities as were so situated that but little or no attrition would 
 result from mastication, and by directing especial avoidance of 
 friction from the brush during the cleansing of the teeth. 
 
 The second objection was by no means so easily disposed of. 
 In fact, after much thought and experimentation, it has been 
 found practically insurmountable. 
 
 Solutions of gutta-percha were tried as "linings" for cavities 
 more than twenty years ago, but the shrinkage from evapora- 
 tion was proved to be even worse than that from cooling, and, 
 as it was indispensable that the material should be heated in 
 order to be properly introduced, it was finally announced that 
 the best gutta-percha fillings leaked, but that this leakage was 
 not detrimental except so far as it permitted slight discoloration. 
 
 The gutta-percha filling materials of the present day are di- 
 vided into three grades : 
 
 First, Those of "low heat," — having sufficient plasticity 
 for manipulation at temperatures ranging from 140° to 200° 
 Fah. 
 
 These are always to be warmed over water, and are particu- 
 larly applicable for filling portions of canals and the bulbous 
 parts of pulp-cavities; and for covering almost- exposed pulps 
 to prevent danger from irritating medicaments employed as ob- 
 
GUTTA-PERCHA. 143 
 
 tundents for sensitive dentine ; and as a first layer of filling iu 
 "deep-seated" cavities of decay. They should be worked with 
 bulbous or serrated instruments, cold and oiled. 
 
 They should not be used for "outside work," as their resist- 
 ance to attrition is quite moderate. 
 
 I refer here exclusively to "low grade" white gutta-perchas, 
 for it is never the case that red gutta-percha base-plate (a very 
 useful and eminently serviceahle filling material) is of higher 
 grade than 150° or 180° Fah. 
 
 Second. Those of "medium" grade, — such as become plastic 
 at temperatures ranging from 200° to 210° Fah. 
 
 In my opinion, these are the hest gutta-perchas for general 
 use, for the various reasons that they can be warmed over 
 water, thus insuring against "heat-rotting" from overheating; 
 that by this means they are prevented from being injured from 
 repeated heating,* and that they possess suf&cient consistence, 
 toughness, and resisting capacity to subserve the purposes of an 
 excellent and durable filling. 
 
 Third. Those of "high heat," — which do not become suf- 
 ficiently plastic for manipulation at less than from 216° to 230° 
 Fah, 
 
 As these will not soften over boiling water, they have to be 
 heated upon a metal or porcelain plate, or over the flame of a 
 spirit-lamp. This requires much care, as it is essential to good 
 results that they be very gradually heated lest they suddenly 
 swell and deteriorate, and that they be not overheated, as then 
 they disintegrate and become "heat-rotted." 
 
 Much of the obloquy which has attached to gutta-percha 
 work has unquestionably been due to ignorance of these facts, 
 and to consequent mismanagement of the material ; and I have 
 never yet conversed with any gentleman that denied the per- 
 manency of gutta-percha fillings who did not heat his filling 
 material either upon a plate of porcelain or metal, or, worse 
 yet, over the flame of the spirit-lamp. 
 
 I would state here that the value of gutta-percha stopping is 
 not to be determined alone by the "heat-test," for it is easy to 
 raise the material to any reasonable degree hy simply increasing 
 the relative quantity of inorganic admixture, but this yqvj in- 
 crease is destructive to value by overloading the gutta-percha. 
 
 *Only small portions of gutta-percha should be placed at a time on the 
 "warmer," &% frequent heating is seriously detrimental to the best stopping. 
 
144 PLASTICS AND PLASTIC FILLING. 
 
 All other things being equal, that gutta-iDercha stopping which 
 gives the highest heat-test with the least admixture of foreign ma- 
 terial is the best. 
 
 Altliough gutta-perclia lias been proved to make a reason- 
 ably good stopping in cavities from which it was found impos- 
 sible to exclude the moisture, it is nevertheless essential to as 
 perfect a filling as can he introduced that dryness he maintained 
 during its introduction. 
 
 If this is not possible, I should recommend the employment 
 of the red hase-plate in preference to any preparation of white 
 stopping, warming it over water, and using cold instruments for 
 its introduction, which should be touched to an oil-pad to pre- 
 vent adhesion of instrument and consequent "drawing" of fill- 
 ing material. 
 
 Note. — The oil-pad is conveniently made by cutting a groove with a small co- 
 rundum wheel, aromnd the end of any ordinary _/?ai top glass stopper, and then, 
 stretching a piece of chamois-skin over the end, securing it by a ligature of book- 
 binder's thread in the groove. The chamois should be of two thicknesses. 
 
 After properly trimming the chamois-skin, a drop or two of sewing-machine 
 oil saturates it, and it is ready for use. 
 
 This little device is essential not only in gutta-percha work, but in connection 
 with the manipulation of tlie zinc-phosphates also. 
 
 In all cases where dryness can be maintained, I should prefer 
 to use the medium heat white preparations. These should in- 
 variably be introduced by means of warm instruments, as the 
 necessary degree of heat for deliberate and accurate manipulation 
 can only be retained to the gutta-percha in this manner. For 
 this purpose a combined gutta-percha and instrument-warmer, 
 of any desirable pattern, should be used. 
 
 The gutta-percha should be heated either over water (" low 
 heat " or " medium ") or upon a metal plate ("high heat " only), 
 but the instruments should always be heated upon a metal plate, 
 — this insures that they shall be hotter than the gutta-percha, 
 and thus that they shall be as warm when taken from the plate 
 and carried to the mouth as was the gutta-percha Vhen taken 
 from its place over the water-bath. 
 
 Another advantage, and a very great one, which is attained 
 by an instrument-warmer, is the ability to heat at one time all 
 the various instruments required in any given operation ; this 
 
GUTTA-PERCHA. 145 
 
 will be found quite desirable, and to result in a great saving of 
 time. 
 
 Again, instruments heated in a flame are very liable to leave 
 traces of soot upon tiie filling, while those heated upon a plate 
 always leave it in a neat and presentable condition* 
 
 The instruments best adapted for the introduction of gutta- 
 percha fillings are — with the occasional exception of a ball- 
 burnisher — certain forms of those used for the manipulation 
 of cohesive foil. 
 
 It is important, however, to note that instruments intended 
 especially to consolidate gold foil by the force of " direct im- 
 pact " are least of all indicated for use in the introduction of a 
 gutta-percha filling, for the principles which govern the durability 
 and value of a foil filling are precisely opposite to those which 
 govern the durability an(^ value of gutta-percha fillings. 
 
 For the perfect introduction and consolidation of foil it is 
 essential that free and fair ingress to the cavity shall be obtained, 
 and for this purpose it is frequently necessary to cut away con- 
 siderable portions of both enamel and dentine. 
 . For the integrity of foil fillings it is regarded as better that 
 the walls of the cavities should possess a reasonable degree of 
 both thickness and strength. 
 
 On the contrary, for the perfect introduction and compacting 
 of gutta-percha, it is not essential that nearly so free ingress to 
 the cavity should be obtained, while it is essential that the 
 largest possible portion of both enamel and dentine should be 
 carefully conserved. 
 
 The most important of this tooth-tissue is just that which 
 should he cut away for foil-worh^ and upon the preservation of 
 this depends, almost entirely, the value of the gutta-percha 
 work, as it guards against attrition, a material which, while it is 
 eminently more tooth-preserving than gold, is wanting in the 
 physical characteristic of resistance to mastication. 
 
 Again, for the integrity of gutta-percha fillings, it is not re- 
 garded as important that the walls of cavities should possess, 
 in much degree, either thickness or strength, as it has been 
 thoroughly demonstrated that some of the- most signal triumphs 
 of gutta-percha have been in teeth in which gold fillings of 
 
 * In finishing fillings, flame-heated instruments should be wiped before- using, 
 10 
 
146 PLASTICS AND PLASTIC FILLING. 
 
 magnificent worlsmansTiip had failed repeatedly, until the 
 remaining walls of the now enormous cavities were almost as 
 thin and frail as letter-paper 1 
 
 Therefore serrated points of such curves and angles as have 
 been found best to meet the requirements in difficult and inac- 
 cessible cavities are those recommended for the introduction of 
 gutta-percha fillings. 
 
 The instruments best adapted for finishing gutta-percha fill- 
 ings are thick and thin, convex or flat burnishers; these, to- 
 gether with the occasional use of a large or small ball-burnisher, 
 will be found to meet all requirements. These should be heated 
 in the same manner as are the pluggers.* 
 
 The filling material and instruments (both plugging and 
 finishing) being properly warmed, the gutta-percha should be 
 taken in small pieces — piece by piece — from its plate by means 
 of a moderately fine probe, and thus carried to the cavity and 
 placed in position. If practicable, each piece should be made 
 to adhere to the wall of the cavity, and then be accurately 
 packed into position by the appropriate plugger, until the cav 
 ity is either entirely lined, or is partly filled, when the com- 
 pletion of the operation is only a question of a short time ; but " 
 when this adhesion of the first pieces is difficult, they should 
 be held in position by the probe until they are made to adhere 
 to the walls by the use of a plugger, when that adhesion should, 
 in turn, be maintained by the plugger, while the probe is care- 
 fully withdrawn. 
 
 It is an important consideration that accuracy in amount of 
 filling material , should be regarded, as thus the minimum of 
 surplus will remain for removal prior to finishing. 
 
 During the removal of surplus material, and the final smooth- 
 ing of the filling, it should always be remembered that the work 
 must be towards the edges of the cavity^ as thus the filling is 
 maintained " flush " and the gutta-percha kept close to the walls. 
 
 While finishing, it will be found that moistute is not only 
 not detrimental^ but in some cases rather advantageous, as it per- 
 mits a smoother cutting of the gutta-percha. 
 
 In dry finishing, only that portion of the filling material 
 which will adhere to the instrument from one touch should be 
 
 * Nos. 2, 3, 6, 7, and 8 of the amalgam set are heated for such use. 
 
I 
 I I 
 
 ,1,1 I 
 
 lllllllllllllllllllllllli 
 
GUTTA-PEECHA. 147 
 
 removed at a time, as retoucliing will complicate and retard 
 progress rather tlian be productive of advance. 
 
 Tests for Giitta-Percha Stopping. — -As there are very numer- 
 ous " makes " of gutta-percha, and as some of these, least wor- 
 thy of confidence as filling material, are advertised as "the very 
 best " of their kind, I deem it important that reliable tests for 
 this valuable aid in saving teeth shall not be wanting, that thus 
 with care in heating, and with proper working, the excellent 
 results which are possible with a good material may not only be 
 confidently anticipated, but fully realized. 
 
 First. Heat-Test. — For the accurate establishment of the 
 "grade"- of any given sample of gutta-percha, it is, of course, 
 necessary to employ a "heat-tester." The illustration suf&- 
 ciently explains itself, as the instrument is, practically, a gutta- 
 percha warmer with thermometer attached. A sufficiently ac- 
 curate arrangement can be made by taking any small tin box, — 
 such, for instance, as are bought with spices, — and cutting an 
 opening in the cover sufficiently large to permit the intro- 
 duction of a thermometer. It should then be partially filled 
 with water and arranged for gradual heating. 
 
 The thermometer should register at least 212° F., while that 
 used for the instrument illustrated registers 230^. No gutta- 
 percha can be serviceably worked which grades higher than 
 220°, and I regard this as uselessly high. At 240°, gutta-percha 
 "heat-rots," and does not regain its previous toughness or in- 
 tegrity, and if at 208° or 209° it softens sufficiently for easy 
 manipulation, it is, if properly constituted, sufficiently resistant 
 to respond to all the legitimate requirements of a good gutta- 
 percha filling material. 
 
 But, as I have said, the value of gutta-percha stopping is not 
 to be determined by the heat-test alone, for it is easy to raise it 
 to the proper " grade-test " by addition of inorganic constit- 
 uents. To further determine its value, then, it is necessary to 
 decide upon the relative quantities of organic and inorganic 
 constituents ; for this we have the " fire-test." 
 
 Second. Fire-Test. — This is done by weighing a small quan- 
 tity — say, a pennyweight — which it is better should be in one 
 piece. This is then subjected to high heat; a convenient 
 method is to place it upon a long-handled iron spoon, and put ■ 
 
148 PLASTICS AND PLASTIC FILLING. 
 
 it on a hot fire ; in a few minutes it takes fire ; burns with a 
 bright blaze ; ceases to burn ; becomes red hot and thoroughly 
 calcined, while it perfectly retains its original shape. It should 
 then be allowed to cool, after which the residuum should be 
 carefully weighed. 
 
 If one pennyweight of gutta-percha stopping has been thus 
 treated, the residuum should weigh a little over nineteen grains 
 if the inorganic constituent is oxide of zinc and the gutta- 
 percha stopping of " low-heat " grade — 1 part G. P. to 4 parts 
 0. z. If the pennyweight tested is "medium heat," and is 
 properly and toughly plastic at 209°, the residuum — if oxide 
 of zinc — should weigh twenty or twenty-one grains — 1 part 
 G. P. to 6 or 7 parts o. z, 
 
 / refer to these proportions and ingredients because a THOROUGH 
 KNEADING of them upon an iron or porcelain slab at a moderate 
 heat — over boiling water — will produce an excellent filling ma- 
 terial of the two most desirable grades. The gutta-percha to be 
 ased is that which is sold in large, dark-brown sheets, resem- 
 bling dark sole-leather, and not that which is light colored, and 
 either in thick pieces or thin paper-like sheets. 
 
 For making of a small quantity of gutta-percha stopping — 
 one to four or five ounces — it is needed that a vessel be ar- 
 ranged for the boiling of water. Upon this is placed a cover 
 of tin, iron, or porcelain — a tin cover with druggist's slab is 
 appropriate — with a tube for escaping steam. Upon the slab 
 or cover is placed the gutta-percha and a portion of the oxide 
 of zinc. As soon as the gutta-percha softens, the zinc powder 
 is gradually kneaded into it. In my experience, this is best 
 done by means of a small wedge-shaped tool of iron — very 
 blunt — set into a small chisel handle, turning the mass with a 
 short, stiff spatula. The incorporation of the zinc should always 
 be in consonance with the maintenance of the toughness of the 
 gutta-percha — never faster — and, after the zinc is all incorpo- 
 rated^ the mass should be thoroughly hneaded for an hour or 
 more, until the stopping is perfectly toughened. 
 
 It is possible that better — tougher — gutta-percha stoppings 
 may be devised in the future, but all unfounded pretensions in 
 that direction may easily be detected by the tests given ; mean- 
 while, those which are made from the formulae, and by the 
 
GUTTA-PERCHA. 149 
 
 metliod given, will be found reliable, as tbey bave been 
 " placed " bj the results of twenty years of experiment, during 
 wbich time the inferior stoppings that have too generally been 
 made, sold, and used, have given so mucb dissatisfaction as to 
 have caused the mass of tbe profession to accept as true the oft 
 repeated solecism, that the making of good gutta-percha stop- 
 ping is one of the "lost arts" ! 
 
 Durability of Giitta-percha. — It was quite a number of years 
 after the entrance of gutta-percha into the list of filling ma- 
 terials before it came to be regarded by any operators as other 
 than subservient for " temporary " work, but, after a time, cases 
 began to multiply in which fillings inserted avowedly as " tem- 
 porary " continued to do good service in such manner as to ex- 
 cite both curiosity and professional interest as to the length of 
 tbeir possible durability. 
 
 It was next noted, as years passed by, that the gutta-percba 
 fillings had actually lasted, in many instances^ longer tban the 
 gold fillings which had been previously introduced. 
 
 Eesults such as these, in my own practice, together with cor- 
 roborative comparison of views with others, induced me to in- 
 stitute an extended course of experimentation in this direction. 
 
 As the result of over fifteen years of careful observation, 
 and witb a basis of over two thousand replacements of gold 
 with gutta-percha, I find that, " properly used," gutta-percha is 
 at least twice as durable as gold, and that in very soft teeth, 
 in selected places, it is fair to presume that it will preserve 
 its tooth at least three times as long as well-introduced gold 
 fillings. 
 
 I wish it to be understood by the profession that I do not 
 make this statement as an opinion, but as an assertion vouched 
 for by long, carefully tabulated records, and as a basis upon 
 which the operators of the future may found a satisfactory, 
 tooth-saving, and comfort- giving practice. 
 
 Cavities in which the use of Gutta-percha (alone) is indicated. 
 — In former years, the cavities in which experience seemed to 
 have conclusively proved the capability of gutta-percha for 
 making a reliable tooth-saving filling were much more numer- 
 ous than at present. At that time all circumscribed cavities 
 upon the mesial or distal faces of soft teeth, as well as many 
 
150 PLASTICS AND PLASTIC FILLING. 
 
 cavities upon tlie labial faces of incisors and cuspids and "buccai 
 faces of bicuspids, and especially large cavities upon the buccal 
 faces of molars near to and even beneath the gums, were re- 
 garded by gutta-percha workers as the places where they 
 achieved their greatest triumphs. 
 
 Gradually, as " combination fillings " began "to be recognized 
 as advanced practice, the legitimate use of gutta-percha alone 
 has become restricted, first, to large cavities approaching the 
 pulps, and having thin, frail walls located upon the buccal faces 
 of molars and bicuspids, either superior or inferior ; second, to 
 circumscribed cavities upon the mesial or distal faces of incisors, 
 cuspids, and bicuspids having reasonably thick walls lahially 
 and huccally (sufficiently so to prevent " clouding " from leak- 
 age), and having an unbroken articulating wall of sufficient 
 strength to resist the action of mastication. 
 
 In soft teeth all these requirements are but infrequently found, 
 and thus it is that, at the present day, the strictly legitimate 
 use of gutta-percha alone as a filling material is almost entirely 
 confined to large cavities^ having thin, frail walls, located upon 
 the huccal faces of molar s."^ 
 
 But it is by no means the case that the use of gutta-percha 
 is confined to cavities in which it alone is indicated as the hest 
 of all filling materials ; for its great value as a " guard " at the 
 cervical portion of cavities between teeth, and as an "inter- 
 mediate " between almost exposed pulps and amalgam or zinc- 
 phosphate fillings; as a complete filling for "taps" either 
 through tooth structure or other filling material, and as filling 
 for " lined " cavities of large size and with frail walls, so situ- 
 ated as not to require a resistant to attrition, has been so satis- 
 factorily demonstrated during the past twenty-five years as to 
 offer every guarantee that such use of it will be eminently 
 satisfactory alike to patients and operators. 
 
 * By coloring gutta-percha stopping with carmine and with jewellers' " rouge," 
 a gum shade can be obtained with which cavities on the labial faces of denuded 
 incisor and cuspid roots may be filled with decidedly artistic effect. 
 
OXY-CHLORIDE OF ZINC. 151 
 
 AETICLB XIV. 
 
 OXT-GHLOBIDE OF ZING. 
 
 IT is now more tlian twenty years since M. Sorel, having de- 
 vised tlie combination of oxide of zinc and a solution of 
 chloride of zinc, suggested its possible value for the " stopping 
 of hollow teeth," as its plasticity, when first mixed, and its sub- 
 sequent rapid hardening and apparent impenetrability to moist- 
 ure, seemed to render it peculiarly applicable. 
 
 Within a couple of years or so after its discovery, my friend 
 Mr. Edward Parrish — afterwards of the Philadelphia College 
 of Pharmacy — received from Europe a sample of the material 
 as prepared for dental use, and, calling my attention to it, gave 
 it to me for the purpose of experimenting as to its real worth. 
 
 At first, it promised to meet certain requirements which were 
 admitted to exist, and which it was very desirable should be 
 better fulfilled ; but it was not long before the action upon it of 
 the fluids of the mouth was recognized as very different from 
 that of ordinary moisture, and, although several varieties of 
 this easily-made compound were soon offered to the profession, 
 they were received with evident caution and with much dis- 
 trust. 
 
 The time required to disprove its claims to be regarded at 
 all favorably as a permanent filling material was not very long, 
 as, within a year after its introduction, many failures had oc- 
 curred, and in some instances the fillings had almost entirely 
 disappeared ; in fact, its proper position was accorded it with 
 remarkable promptitude. 
 
 Recipes for its manufacture, containing oxide of zinc, silex, 
 borax, alum, ground glass, etc., as components of the powder, . 
 together with deliquesced chloride of zinc, or metallic zinc dis- 
 solved in muriatic acid, combined with soluble glass, for the 
 fluid, were freely given at conventions and published in the 
 journals; but its employment has always been confined, by those 
 best informed in regard to it, first, to the obtunding of sensi- 
 tive dentine in superficial or ordinary cavities of decay, using 
 it for this purpose as a temporary filling ; second, to the oc- 
 casional filling of frail incisors, cuspids, and bicuspids, for as 
 
152 PLASTICS AND PLASTIC FILLING. 
 
 long a period as it would last, but avowedly with tlie intention 
 of frequent renewal ; and, third, as a lining for cavities having 
 thin walls, and as a filling for the larger portion of very large 
 cavities, when it was proposed to fill externally either with 
 amalgam or gold. 
 
 Both recipes and uses have remained always practically the 
 same ; the adjuncts of ■sttess^ alum, ground and soluble glass, 
 etc., have quietly become, to a great extent, ignored, but the 
 "■6xide^of"zin^and borax powder, and the solutions of chloride 
 or muriate of zinc, are the same to-day as when they were 
 given us twenty odd years ago. 
 
 With all its deficiencies, oxy-chloride^ under a multitude of 
 names, such as os artificial, osteo-dentine, crystalline, rock, 
 agate, acme, and various other cements, together with a numer- 
 ous list called after their makers Houghton's, Eobert's, Smith's, 
 Fletcher's, Poulson's, Franzelius', etc., has steadily been given 
 in response to increasing demand, until the quantity which is 
 now used is something incredible. 
 
 In this connection it is truly remarkable that this compound, 
 so worthless for general purposes, so utterly unreliable as a fill- 
 ing material, so almost completely ignored by the "plastic- 
 filler," should be used in such extraordinary amounts. It 
 seems as though, in desperation, those who have patronizingly 
 styled gutta-percha " an excellent material for temporary fill- 
 ings," and have decried amalgam as an " abomination, used only 
 by incapables, and endured only by imbeciles," have been forced 
 to content themselves with this miserable apology for a plastic 
 filling. They .have discussed it periodically^ even within the 
 past year, repeating again and again the few things that could 
 be said of it ; they have spoken of its " proper manipulation " 
 just as though it were not far easier to work than either gutta- 
 percha or amalgam. It has been not only admitted to be a 
 good thing under gold, but a most* excellent device, " well 
 worthy of much consideration ; " this, however, was not so re- 
 garded until after the plastic-fillers had been so using it under 
 gutta-percha and amalgam for more than a dozen years I It 
 was finally " accepted " concomitant with a modified oxy-chloride 
 — so stated — but the plastic-fillers never knew of any such 
 modification; and thus, as the plastic-fillers have, gradually, 
 
OXY-CHLOEIDE OP ZINC. 15S 
 
 most completely ignored oxj-cliloride of zinc as a filling ma- 
 terial^ the gold- workers have come to using it by the hundred- 
 weight. 
 
 . Various efibrts have been made for the " improvement " of 
 oxy-chloride ; ground feldspar, pulverized French chalk, oxide 
 of tin, and many other like ingredients, have each been tried 
 and abandoned. The most of these were found to act preju- 
 dicially, and none of them produced any decided improvement 
 over a well-prepared, properly calcined " Sorel Cement." 
 
 Some four or five years ago, a method was proposed for treat- 
 ing oxy-chloride of zinc fillings by rubbing them with heated 
 talc; points of French chalk (talc) were secured in crayon- 
 holders, and, after being heated over a spirit-lamp, were used to 
 smooth, dry, and harden the surface of the fillings. These 
 were afterwards burnished with agate burnishers, and a pecu- 
 liarly beautiful effect was thus produced. 
 
 It was found, upon very limited trial, that the whole thing 
 was deceptive, and that there was no value in it. The first 
 fillings which I introduced and finished by this process — 1876 
 — began to show evident signs of wear in less than a month, 
 and in less than a year positive proof of its general inutility 
 was afforded to such extent as to warrant its total abandon- 
 ment. 
 
 It is unquestionably true that some of the oxy-chlorides 
 are better than others, for they are more thoroughly com- 
 pounded and more carefully prepared ; but it nevertheless 
 remains that the best of them is entirely unreliable, and that 
 no one of them is deserving of rank as a filling material. 
 
 But oxy-chloride has great value for the plastic-filler as a 
 " liner " of cavities prior to filling. It was early noted that 
 the doubts which were expressed as to the possibly deleterious 
 effects of the material upon tooth-bone were proving more and 
 more groundless. It was early noted that the " chalky " con- 
 dition of dentine, which was confidently prognosed as likely 
 to ensue, did not appear, but that, on the contrary, this struct- 
 ure was maintained in sing ular integrity. As year after year 
 passed by, it was noted, with increasing interest, that decay was 
 never seen under oxy-chloride of zinc, and thus it was that in 
 "plastic dentistry" it advanced from the position of a mere 
 
154: PLASTICS AND PLASTIC FILLING. 
 
 foundation — an advantageous, non-conducting, occupant of spare 
 
 — to tlie dignity of a complete " liner," a preventive alike of dis- 
 coloration and decay. 
 
 It is only two years since Prof. D. D. Smith read tlie paper 
 wliicli first openly advocated tlie use of oxy-cliloride " linings " 
 from the therapeutic stand-point ; a matter of vital importance, 
 a point for grave consideration, and one which it seems to me 
 cannot be controverted.* 
 
 It is true that oxy-chloride of zinc remains, most persist- 
 ently in some cases, doing duty as a filling, where everything 
 else seems to fail ; but these instances are so very rare, and the 
 indications which point to this possibility are *so entirely un- 
 known, that this fact alone stamps the filling as the most unre- 
 liable of all, as it will probably fail very soon, but may possibly 
 last for many years. 
 
 Oxy-chloride of zinc fails in two ways ; first^ and least nota- 
 bly, from attrition ; for this reason it usually lasts best in cavi- 
 ties upon articulating faces, where it sustains the wear incident 
 to mastication ; and, second^ and most notably, from solution or 
 disintegration at the cervical portion of the filling. At this 
 point, ^^ fails as decidedly as does tooth-bone — soft structure 
 
 — at the cervical margins of metallic fillings, especially those 
 made of gold. 
 
 This matter of respective failure, in this connection, is most 
 interesting and instructive to the student of the " compatibil- 
 ity " theory ; for, observation shows, that with gold as a filling 
 material, the cervical margin of the filling remains intact, while 
 the contiguous tooth-structure is markedly decayed ; and that 
 with oxy-chloride as a filling material the cervical portion of 
 the tooth remains comparatively intact, while the filling is rap- 
 idly disintegrated. 
 
 To the plastic-filler, whose thoughts are ever upon tooth- 
 salvation, this fact alone would decide the relative value of the 
 two materials as tooth-savers, and he would rather renew fill- 
 ings as often as required than permit successive decay to finally 
 destroy the tooth ; for, he reasons, filling material is obtainable 
 in any quantity, but tooth-bone is limited in amount, and teeth 
 are limited in number ; and yet he does not stop at this deci- 
 sion, for experience has taught him that other materials are 
 * Read August, 1878 ; published in " Cosmos," October, 1878. 
 
OXY-CHLORIDE OF ZINC. 155 
 
 infinitely more reliable for filling at this point — materials like 
 submarine amalgam, tin, or, perhaps best of all, gutta-perclia. 
 And therefore it is, that although in some mouths, where oxy- 
 chloride has been proven to do well, a plastic-filler might use 
 it for an articulating filling, yet he would never think of em- 
 ploying it for filling approximal cavities or cavities approach- 
 ing near to, much less impinging upon, the gum. 
 
 From an experience of twenty years, I am taught never to 
 use oxy-chloride of zinc as a filling material ; that is, as a ma- 
 terial for filling, entirely, a cavity of decay ; or for filling a 
 gutta-percha or varnish-lined cavity in such manner as would 
 leave the oxy-chloride exposed to the action of the fluids of 
 the mouth. 
 
 But, as I have stated, this material is regarded as inval- 
 uable for use as a " lining " to cavities having thin, frail 
 walls, and it is for this purpose, and for this only, that I ever 
 use it. 
 
 Oxy-chloride of Zinc, as prepared for dental use, consists 
 of a powder and a fluid. Portions of each, being mixed to- 
 gether into a thick creamy paste, soon form a reasonably hard, 
 whitish cement. The powder is made by thoroughly rubbing .-^• 
 together, in a small mortar, two grains of borax/andTour^enny-"^y^^ C 
 weights of oxide of zinc. I give these proportions in troy 
 weight, becaU'Se the weights sold with dentists' scales are 
 "Usually of that denomination. These are then placed in a 
 small crucible, and subjected to a glowing red heat for from 
 seven to ten minutes; in this way is formed a "frit," which, 
 when cool, is finely pulverized by again rubbing it in the 
 mortar. 
 
 Sixteen pennyweights of oxide of zinc are then calcined for 
 three or four minutes, at a moderate red-heat, and allowed to 
 cool. This calcined oxide is then gradually added to the pul- 
 verized frit in the mortar until all is thoroughly rubbed up 
 together. The zinc is calcined for the purpose of freeing it 
 from the moisture which it always absorbs when exposed to 
 the air, and the powder should be kept in a tightly-stopped 
 bottle in order to maintain this calcined condition. It is 
 added in quantity, to the frit, which is sometimes quite yellow, 
 ■ for the purpose of securing the whitest possible oxy-chloride ; 
 
156 PLASTICS AND PLASTIC FILLING. 
 
 this can be afterwards shaded, if desired, by the addition of 
 .^»eme-yello"w. ^ cJl^^r^ 
 
 The fluid is made either by saturating muriatic acid with 
 metallic zinc — allowing the solution to clear and then decant- 
 ing — or, by dissolving half an ounce of chloride of zinc in 
 two and a half to three drams of water ; the latter is the 
 easier and, I think, the better method. Considerable heat is 
 generated by this dissolving, therefore the bottle in which it is 
 done should not be too tightly stopped. After several shakings, 
 the contents should be allowed to settle for some days, when 
 the perfectly clear portion of fluid should be poured ofi' for 
 use. If it does not clear, filter the solution. 
 
 For the mixing of oxy-chloride of zinc, and, indeed, any of 
 the zinc plastics, a piece of plate-glass, one-fourth of an inch 
 thick, two or two and a half inches wide, and three or three 
 and a half inches long, will be found very convenient and de- 
 sirable. Upon this is placed one or more small portions of 
 fluid, each portion separate from the others, distant an inch or 
 so ; a sufficient quantity of the powder is then poured upon 
 the slab, and the materials are ready for mixing. 
 
 It is usually directed that the cavity be filled with oxy-chlo- 
 ride, and that a sufficient length of time be given for the com- 
 plete hardening of the material — a day or more — when, it is 
 said, it should be burred out as desired, and the covering filling 
 of gold or amalgam be made. These directions, together with 
 the teaching that the main objects accomplished are the secur- 
 ing of a non-conducting medium which largely fills the cavity, 
 and thus prevents the necessity for so much irritation to the 
 surroundings and so great expenditure of time in the introduc- 
 tion and consolidation of the gold filling, are not at all in con- 
 sonance with the ideas of a plastic-filler, for it is recognized 
 that oxy-chloride of zinc is a notable shr inker ; that it begins 
 to shrink in a short time after it is introduced, and that it con- 
 tinues shrinking for several days ; that this shrinkage must 
 result in a defective lining, and it is therefore taught, from the 
 " plastic " stand-point, that the oxy-chloride should be intro- 
 duced in small portions, and that it should be pelleted — see 
 " pelleting," in Technicalities — into position against the walls 
 of the cavity. 
 
OXY-CHLORIDE OF ZINC. 157 
 
 Furtliermore, it is not regarded that tlie raain objects secured 
 are non-conduction and the filling of the cavity, in large de- 
 gree, with a material which will prevent undue irritation from 
 dental manipulation, for in plastic filling oxy-chloride is never 
 used for its non-conducting characteristic, and is never needed in 
 hulk, but is rather desired in its thinnest possibility, as obviating 
 shrinkage, and none of the materials used in filling, necessitate 
 any dental irritation. 
 
 In plastic dentistry, the main objects which are regarded as 
 secured by the " lining " with oxy-chloride are, first, exemption 
 from further decay ; second, maintenance of color, improvement 
 of color in discolored teeth, and prevention of tooth discolor- 
 ation from filling materials liable to produce such result ; third, 
 the securing of solid support for amalgam, when gutta-percha — 
 a yielding material — is used as a non-conducting pulp protector 
 or guard for cervical edge of cavity ; and, fourth — incidentally 
 — as a strengthener to frail walls which would be liable to 
 fracture during the progress of " treating " a tooth. 
 
 Oxy-chloride of zinc, though used with impunity in pulpless 
 teeth, — pulp cavities filled with gutta-percha, — should be used 
 with much caution in teeth of soft structure and non-recuper- 
 ative attributes, containing living pulps. Its introduction into 
 cavities in such teeth should always be preceded by arnica 
 plaster ; adhesive plaster ; gutta-percha, — " low heat," — or 
 oxy-sulphate of zinc, as, by these means, pulp irritation, from 
 the chloride of zinc fluid, is prudently guarded against. 
 
 Oxy-chloride of zinc is best mixed by approaching a portion 
 of powder to the drop of fluid, and pushing it into it by the 
 point of the spatula. It is taken up, so to speak, by the liquid, 
 and in this way an approximate to the required proportions of 
 fluid and powder is obtained, when the addition of a very small 
 quantity of powder will make, by the usual spatula mode of 
 mixing, a creamy mass of thick viscidity, which, taken upon 
 the end of the spatula, should be placed in position in the cav- 
 ity and pressed gently against the wall. 
 
 Having pellets of cotton wool in readiness, these should be 
 taken and used as described in " pelleting." In a few minutes— • 
 five or ten — the lining will be sufficiently " set " to proceed with 
 the covering filling. 
 
168 PLASTICS AND PLASTIC FILLING. 
 
 Tlie experience wliicli I have had. in the direction of "lining" 
 teeth with oxy-chloride, makes it seem to me strange to hear 
 the therapeutic action of filling material denied, and still more 
 strange to see the- constant presentation of certain qualities as 
 " resistance to the fluids of the mouth," " resistance to attrition," 
 etc., as characteristics of a material which are essential to the 
 saving of teeth. The idea is ever tacitly accepted, that a cavity 
 of decay must be filed with ONE material which shall combine 
 all the varied attributes needed for success, totally ignoring the 
 palpably presented fact, that materials ivhich possess certain tooth- 
 saving attributes, and are deficient in others, can be utilized IN 
 THEIR PROPER PLAGES, while these, again, can be protected by 
 other materials, which, though deficient in essentials possessed by 
 the former, are, in wonderful degree, possessed of the very essen- 
 tials which, in these, have been found wanting. 
 
 I have hundreds of cavities, in the teeth of my patients, 
 from which gold fillings, introduced, by some of the very best 
 operators of our country, failed from surrounding decay, and 
 literally dropped out, in from two to five years, and in which 
 amalgam fillings had been tried, some of them by the same 
 operators, with but little better success, in which " linings " of 
 oxy-chloride, protected by amalgam coverings, have done good 
 service for from six to twelve years, and are yet in such con- 
 dition as bids fair to afford years of service during the future. 
 
 I cannot dismiss the subject in hand without referring spe- 
 cially to oxy-chloride as a restorer of color to discolored teeth. 
 It has been my experience that discolored teeth in which 
 "bleachers" have been used, gradually lose the renewal of 
 beauty which had been afforded them, and that the after dis- 
 coloration is often worse than the first. For this reason I have 
 long abandoned this method of " whitening " teeth, only resort- 
 ing to it for an occasional experiment, as various materials 
 or combinations have been successively recommended. Of all 
 these, I have never yet tried any one which has proved so 
 satisfactory, and has maintained so generally a permanent ef 
 feet, as oxy-chloride of zinc. 
 
 Quite early in its use, the capability which it possesses of 
 producing a marked whitening of teeth was duly noted. In 
 many cases of exc tdingly frail front teeth, with very thin 
 
OXY-CHLORIDE OF ZINC. 159 
 
 labial enamel, its introduction caused sucli " spottings " of 
 
 white through this trans'parent tissue as to render it necessary, 
 
 for beaut}^, that tlie filling sbould be removed and replaced bj J 
 
 an oxj-cbloride wbicb bad been shaded hy KHiromA-yellow^oS^- "" 
 
 pressly for this purpose. ^ 
 
 It was an easy deduction that thus indicated the worth of a 
 white oxy-chloride as an adjunct to the old-fashioned prepared 
 chalk and the scraped French chalk — talc — which have been 
 used for half a century to remove the heavy discoloration 
 prior to "bleaching," and which, with me, have still retained 
 their value ; therefore, I would now recommend, as the result 
 of fifteen years' experience, that the vchitening of teeth — :I 
 discard the term "bleaching" as inappropriate — should be 
 accomplished by first entering thoroughly and removing, as 
 much as possible, consistent with maintenance of strength of 
 tooth, all discolored dentine, especially at the cervical portion ; 
 then, after proper treating, the canal should be filled for three- 
 fourths its length from the apical foramen. If this is done 
 with cotton, it should be perfectl}^ protected by gutta-percha 
 covering.* 
 
 The cavity should now be packed with prepared chalk or 
 pulverized — scraped — French chalk, and this should be cov- 
 ered either with small pellets of cotton, tightly packed, dry, 
 and afterwards moistened with varnish of gum-sandarac, or 
 with an oxy-chloride or zinc-phosphate capping. The chalks 
 act to remove the organic discoloration just as they do in the 
 usual household application of these materials for removal of 
 such stains from dress goods, floors, carpets, etc. ; and, indeed, 
 I was told, more than thirty years ago, that it was the domes- 
 tic use of chalks for this purpose that first suggested their like 
 employment in dentistry. 
 
 A few days should be given for the action of the chalk, when 
 it should be removed, and, if indicated, a second application 
 should be made. When the color has been approximately 
 restored, the tooth should be placed under rubber, and the 
 cervical portion " lined " with a thin film of very white oxy- 
 chloride. The object of this thin lining is, that very little, if 
 any, pain is induced by the attenuated oxy-chloride, while the 
 pain which is apt to result from a bulk of this material — even 
 * " Temporary stopping" material is better than gutta-percha. 
 
160 PLASTICS AND PLASTIC PILLING. 
 
 in pulpless teeth — is sometimes very considerable, and may be 
 of some length of duration. 
 
 After this lining has " set," a process usually requiring fifteen 
 or twenty minutes, I prefer to fill the cervical portion, as far 
 down as the edge of the lining, with gvitta-percha, as this ma- 
 terial is easier of removal, if, at any future period, it is deemed 
 desirable to relieve peridental irritation by entering the canal. 
 
 The crown portion should next be lined with oxy-chloride, 
 so shaded as to result, if possible, in a color lighter than that 
 of the adjoining teeth. The reason for this effort is that the 
 moisture will detract somewhat from the color attained, and the 
 final result will thus be exactly that which is desired, q^i^i^m^— 
 
 Oxy-chloride is usually shaded with i^isi^m^jellow/sind, very 
 rarely, with lamp-black. ^ 
 
 The tooth may now be filled with an amalgam made from 
 one part of " contour " and two parts of " facing " alloy, if a re- 
 sistant filling is required ; or it may be filled with gutta-percha, 
 if the filling is not exposed to attrition, or if the tooth has been 
 intermittingly troublesome and may possibly require an occa- 
 sional relief dressing. 
 
 AETICLE XV. 
 OXY-SULPHATE OF ZING. 
 
 THIS plastic preparation is, even more than the oxy-chloride 
 of zinc, to be regarded as not at all useful as a filling ma- 
 terial^ but, like the oxy-chloride, it is a most valuable adjunct 
 in its proper place. This also consists of a powder and a fluid. 
 The powder is composed of calcined sulphate of zinc, one part, 
 and calcined oxide of zinc two, and sometimes three parts. 
 
 The sulphate of zinc is first thoroughly calcined, at a glowing 
 red heat, and, when cool, is reduced to a fine powder by hard 
 rubbing in a mortar. The oxide of zinc is then calcined as if 
 for oxy-chloride powder, and, when cool, is added to the finely 
 powdered sulphate. The powder should be kept in a tightly 
 stoppered bottle. 
 
 The fluid is made by dissolving fifteen grains of gum-arabic 
 in a half ounce of pure water, and, when completely dissolved, 
 
OXY-SULPHATE OF ZINC. 161 
 
 adding one grain of sulphite of lime. Filter solution tlirougli 
 absorbent cotton. 
 
 Oxy- sulphate of zinc is probably one of the best pulp pro- 
 tectors and pulp cappers which has ever been used ; it is easy 
 of adaptation, quite as much so as gutta-percha, arnica plaster, 
 adhesive plaster, or the oxide of zinc and oil of cloves pad; but 
 it possesses certain peculiarities which are very valuable, and 
 which appertain to no other capper or protector, except, per 
 haps, plaster of Paris, which it very much exceeds in rapidity 
 of setting and in density after it has become hard. Together with 
 these attributes, it is not only perfectly non-irritating alike to 
 sensitive dentine and to the dental pulp, but, from its admixed 
 sulphate of zinc, is accredited, with much show of reason from 
 extended experimentation, with therapeutic value as an astrin- 
 gent, antiphlogistic pulp preserver. 
 
 This is mixed upon the glass slab already described, muck 
 in the same manner as is oxy-chloride, but it should be mixed 
 much thinner ; indeed, it should be but little more than milky 
 in its consistency, and certainly not thicker than very ordinary 
 cream.. 
 
 It should then be worked with the spatula until it hegins 
 to give the least perceptible evidence of thickening, when it 
 should be taken upon the end of the spatula and placed 
 accurately in position in the cavity b}^ being pushed off the 
 spatula by a moderately fine probe. 
 
 It will adhere nicely to the dentine if it is properly manipu- 
 lated, and, in its still yieldingly plastic condition, can be spread, 
 as required, by careful working with the imj 6nd of the probe. 
 It should not be worked after it ceases to flow, comparatively 
 easily, under this instrumentation. 
 
 Another method, and a very excellent one, particularly 
 adapted to difficult and inaccessible capping, is that of pre- 
 paring a pellet of cotton, no larger than the head of a small 
 pin^ which should be dipped in the milky zinc-sulphate imme- 
 diately after it is mixed. The tiny capping is then gently 
 placed accurately in position, and will be readily secured in 
 place by touching its edges with a small, smooth-ended instru- 
 ment. 
 
 It now requires a few minutes — from five to fifteen — to set 
 11 
 
162 PLASTICS AND PLASTIC FILLING. 
 
 sufficiently for progressive work, and then permits the intro- 
 duction of oxj-chloride side linings, or of amalgam or gutta- 
 percha fillings. 
 
 This operation is one requiring considerable dexterity, and 
 some practice, for its acceptable accomplishment; but with 
 these it becomes a neat and most reliable method for pro- 
 tecting almost exposed and exposed pulps. 
 
 AETICLB XVI. 
 ZINC-PHOSPHA TE. 
 
 THE attempted utilization of the acids of phosphorus for 
 the purpose of compounding filling materials is now of quite 
 respectable antiquity when compared with the still moderate 
 age of dentistry as a profession; for the old recipe of Oster- 
 mann, published in 1832, may almost be regarded as cotempo- 
 rary with the " silver paste " of M. Taveau. 
 
 This formula, for which I am indebted to Dr. De Montreville, 
 is as follows : 
 
 " Take 13 parts of finely powdered lime and 12 parts of 
 anhydrous phosphoric acid. This compound is moist during 
 .the mixing, and while in that condition is to be put into the 
 cavity of the tooth, the cavity being prepared in the usual 
 manner. The filling must be used in one or two minutes 
 after it is made, as it almost instantly hardens. The lime 
 must be caustic lime, and chemically pure." A second old 
 formula, furnished me by the same gentleman, reads thus : 
 
 " Mix equal parts of finely-powdered silicate or fluate of 
 lime and alumina, with a sufficient quantity of water to make 
 a homogeneous paste. This is to be introduced into the cavity 
 of the tooth to be filled, and the drying of the mass is to be 
 aided by warming it with heated instruments." 
 
 From these two initial cements the phosphoric filling ma- 
 terials of the present day seem to have gradually developed, 
 but it is only during the past fewyears that the attention of the 
 profession has been especially directed to them. The cements 
 of Eostaigne, Poulson, Grass ^nd Worff, Fletcher, and others — 
 
ZINC-PHOSPHATE. 163 
 
 a series of variably good materials — were quickly followed by 
 many, more or less worthy, imitations of the genuine article. 
 All the former are entitled to the appellation of " Zinc-phos- 
 phates," for they have the obdurate nitrate of zinc as their 
 powder, which is made into paste with variously, and in some 
 instances accurately and scientifically, prepared fluid or crystals 
 of such form of phosphoric acid as makes reasonably durable, 
 and sometimes remarkably durable fillings ; while many of the 
 latter are merely oxy-phosphates of zinc, — for their powder 
 is nothing but calcined oxide of zinc,^— a material incapable, so 
 far as is known, of making a resistant cement ; or yet worse, a 
 mixture of oxide of zinc and oxide of tin ; while the fluid is 
 merely glacial phosphoric acid dissolved in water and either 
 evaporated to the " desired " (?) consistence or permitted to 
 form a natural separation, by time, and then decanted. 
 
 The former of these methods is eminently unscientific, as ex- 
 periment proves it to be impossible ever to repeat the process 
 with a known result ; and eminently unsatisfactory, as none of 
 the results make a cement which responds to a single "test" 
 for a good " zinc-phosphate." 
 
 By the latter method, with the nitrate of zinc powder, an 
 approximate to a good result is produced, but with the calcined 
 oxide of zinc only a poor cement, at best, is made. 
 
 The amount of work which has been done in the direction 
 of these cements is something extraordinary ; and it is equally 
 noteworthy that only those whose " contributions to knowl- 
 edge," in this line of experiment, have proven that they knew 
 nothing about it, have ventured to place themselves upon the 
 record ! 
 
 There is no other plastic filling material in regard to which 
 I have had such hesitancy in both speaking and writing, even 
 in the familiar way of correspondence, and no direction in which 
 I am better satisfied to be regarded as " not posted," for I feel 
 sure that, so far, those who know most of it, recognize that 
 they know but little, while, unfortunately for the society records, 
 and for the members of the profession who depend upon them 
 for information, those who know nothing of it, have freely 
 given all they know. 
 
 I have been for years in constant correspondence with those 
 
164 PLASTICS A]SrD PliASTIC FILLING. 
 
 whom I had reason to suppose most earnest and best informed 
 in this work, and time and again have we thought that " suc- 
 cess " was. to reward our efforts ; but the ruthless evidence of 
 deteriorating fluid, and crystals, and disintegrating fillings has 
 repeatedly dampened our ardor imtil it has wellnigh, at times, 
 extinguished our zeal. 
 
 But ever before us have been the provings of the possibility ; 
 many of us have seen the fillings of good "zinc-phosphate" 
 which have done two, three, four, and more years of service, 
 and are yet, practically, as good as when they were made. I 
 hav6 fillings in the mouths of patients, upon the articulating 
 faces of which I punctured little indentations, that after two 
 years of service remain just as they were at first. I have 
 fillings in mouths in which beautiful gold-work failed largely, 
 in from one to two years, and in which zinc-chloride lasts but a 
 few months, that now, after more than two years of trial, are 
 about as good as when introduced. 
 
 These results are mostly from Poulson's rock-crystal zinc- 
 phosphate — a material which has not been produced of late, 
 but towards the reproduction of which stremious and promis- 
 ing efforts are being made. 
 
 It is from the behavior of this material, which has been 
 tried and found worthy^ that I collate the "tests" for a "good" 
 zinc-phosphate, and my experience indicates that just in pro- 
 portion as any of these preparations respond approximately to 
 the tests given, so will fillings made from them average durable 
 and satisfactory. 
 
 Like the other zinc plastics, the zinc-phosphates are prepared 
 for use in the form of a powder and fluid or crystals. 
 
 The powder is made by treating oxide of zinc with nitric 
 acid, evaporating to dryness, calcining, and pulverizing. 
 
 This work, so far from being an affair of two or three hours, 
 is a matter of several days and nights, consecutively, for the 
 production of even a moderate amount. 
 
 The powder thus prepared is readily distinguishable from 
 the worthless oxide of zinc powders by its dry^ quick fineness ; 
 a. peculiar cracking apart of the bulk of powder as the bottle 
 containing it is slowly revolved ; by its feeling of slight grit, 
 
ZINC-PHOSPHATE. 165 
 
 be it never so fine, and bj its decided weight as compared with, 
 any oxide of zinc powder. 
 
 This powder, with a good fluid or crystal phosphoric acid, is 
 capable of making a very resistant cement. 
 
 ' So far as I am aware, all the acid menstrua are fluid when 
 first made ; but, after being prepared, the changes which super- 
 vene are peculiar in character and very numerous. In most 
 cases, the limpid fluid or syrup retains its clearness only a few 
 days or weeks, when, gradually, a cloudy appearance is observ- 
 able; this increases until a thick, whitish paste results; this 
 again separates into sediment and supernatent limpid fluid. 
 
 It has been stated that such preparations make " equally 
 good " cements during any and all of these phases ; but experi- 
 ence proves that it would be more correct to regard them as 
 all equally had, for no cement made from any such fluid or 
 paste does any credit to " zinc-phosphate." 
 
 In some fluids the limpid fluidity changes to turbidity, and, 
 without passing through the paste form, gradually separates 
 into sediment and clear fluid. This fluid " keeps" indefinitely, 
 and, with a proper powder, makes a cement which may appro- 
 priately be styled a " bastard " zinc-phosphate. It has a family 
 likeness to the genuine article, but its working, and its com- 
 paratively prompt disintegration in the mouth, proves its ille- 
 gitimacy. 
 
 Occasionally a clear fluid is made which, for a time, is as 
 good as fluid can be. It maintains its integrity surprisingly ; 
 it works quick and well ; it makes a reasonably good cement ; 
 but it gradually, and without apparent change, except to an 
 expert, deteriorates. This change is merely one from quich 
 fluidity to slight viscidity. It is scarcely perceptible except to 
 a practised eye, but is readily noted by almost any one when 
 attention is directed to it. When this change takes place, the 
 working of the cement also changes entirely. It works easier ; 
 sets much more slowly; becomes, generally, much more accepta- 
 ble, and of such material thousands of unreliable fillings have 
 already been introduced. 
 
 Up to the present time it has not been peovejst that any fluid 
 makes as good cement as does crystal acid. But here, again, is 
 much circumspection necessary ; for it seems to be essential to 
 
166 PLASTICS AND PLASTIC FILLING. 
 
 " excellent " results tliat the sj^rupj acid should change to "hard, 
 rock-like crystals, and not to feathery, flaky, waxy crystals. 
 
 When rock-like crystals are obtained, they are to be melted 
 in very small quantity, and with very great care, to prevent 
 ebullition, over the flame of a spirit-lamp. It has been directed 
 to use a spoon of platinum for this purpose; but this is not 
 requisite, as any ordinary teaspoon is appropriate. 
 
 When melted, the crystals assume a clear, sticky viscidity. 
 This syrup is then to be scraped from the tip of the spoon- 
 bowl — where it is best that it be placed for melting — onto 
 the glass-mixing slab. The powder should noiv be poured out, 
 as thus a moment is given the syrup for cooling. If mixed 
 while the syrup is hot, the zinc-phosphate sets almost instantly, 
 indeed, so rapidly is this change sometimes effected, and with 
 such evolution of heat, that it is dangerous to take the mass in 
 the fingers lest one be burned. 
 
 It must be understood that the illustrations given of changes 
 and peculiarities of fluid and semi-solid menstrua are merely 
 a typal few of the many which have been recognized, and which 
 are constantly being added to, and that it would be wholly un- 
 profitable to continue citations of them, as practitioners cannot, 
 by this means, be made judges of the comparative value of the 
 various zinc-phosphate and oxy-phosphate preparations. 
 
 It is only by " working-tests " that this can be decided, and it 
 is for this reason that I shall direct particiflar attention to them. 
 My facilities for noting these have been very extensive, for I 
 have been in receipt of all the preparations made, both in 
 Europe and our own country, for nearly three years ; of these 
 I had introduced, more than a year since, over five hundred ex- 
 perimental fillings, all tabulated, and all under frequent inspec- 
 tion, and from this observation I have obtained such data as I 
 have reason to believe will give zinc-phosphate — at least, as 
 now made — its proper value. 
 
 It has been intimated that the zinc-plastics seem destined to 
 supersede amalgam ; but I regard such opinion as without the 
 slightest foundation, and based alike upon ignorance of the 
 progress which has been made in amalgams, and of the defi- 
 ciencies which notably characterize the oxy-chlorides, the oxy- 
 phosphates, and even the best of the zinc-phosphates. 
 
ZINC-PHOSPHATE. 167 
 
 It is true that tlie zinc-plastics laave a better color tlian amal- 
 gam, but in no other respect do thej compare favorably with 
 it as filling materials. 
 
 When a zinc-phosphate is really "good," it is very good; 
 ancl, although it is much more difficult to work than any other 
 plastic filling material, yet the practice which has, necessarily, 
 to be given to overcome this, is by no means unworthily be- 
 stowed, for the durability of a good zinc-phosphate filling is at 
 least from three to five times that of the average oxy-chloride 
 of zinc filling, and its density makes it of great value even on 
 the articulating faces of teeth.* On the contrary, poor zinc- 
 phosphates, and even the best oxy-phosphates, are, comparatively^ 
 worthless materials. They are better than the average oxy- 
 chlorides, but compared with good zinc-phosphates they are 
 quite inferior. They are, moreover, very alluring and equally 
 deceptive ; for they mix nicely, work easily, set slowly, and 
 apparently make very nice fillings ; but it requires only a few 
 months — six to twelve — to demonstrate that, although they 
 promise much^ they perform but little. 
 
 I wrote of them, more than a year since, that they made "a 
 thick, tough, doughy mass ; they are easily and handsomely in- 
 troduced into cavities ; they set slowly, and thus give time for 
 careful manipulation ; they finish nicely, and they make miser- 
 able, good-for-nothing fillings!'''' and the opinion then offered 
 has been most fully corroborated by the results which have 
 since been noted. 
 
 Mixing Zinc-phosphate, 
 
 In mixing zinc-phosphate /or " ^esilmp'," a portion of fluid 
 equal to one or two drops, or ten grains of crystals, melted, 
 should be placed upon a glass slab, and more than sufficient 
 powder should be poured out near to it. A bulk of powder 
 ahout equal in size to the bulk of fluid should then be mixed 
 with the fluid by means of a suitably shaped steel spatula. 
 This should make a mixture of a thick, creamy consistence. 
 
 Then a little more powder should be added and quickly and 
 forcibly made into mass by thorough spatulation. 
 
 It is possible that yet a little more powder may be required 
 to give the mass the desired consistence for strength and dura- 
 * Especially on articulating faces of teeth. 
 
168 PLASTICS AND PLASTIC FILLING. 
 
 bilitj, but it is better tliat the " mix " be a proper one by tlie 
 two additions of powder. The reason for this is, that zinc- 
 phosphate is a quick-setting hydraulic cement, and the chem- 
 ical combination is one that commences promptly, and should 
 be the least possibly interfered with during its progress by the 
 successive introduction of ingredients. 
 
 The mass should be of &-putty-like consistence, though some 
 varieties are directed to be made "stiff." In "testing," these 
 should be made according to directions, so as to give them the 
 benefit of every possibility. 
 
 The mass should then be scraped up on the spatula and taken 
 from it by the thumb and forefinger.* 
 
 ^YiQ first test for a "good" zinc-phosphate is, that it requires 
 decided force to take it from the spatula. 
 
 The mass should then be Tcneaded — NOT ROLLED — by two 
 or three gentle motions of the thumbs and forefingers. The 
 warmth of these makes the mass slightly more plastic^ and the 
 hneading is of great value in producing homogeneity. 
 
 The fingers should be scrupulously clean, or the material will 
 be soiled. 
 
 The mass should then be upon the end of the forefinger of 
 the left hand, from which it should be removed by the spatula 
 and placed on the palm of the same hand, and then gently 
 rolled into a round, pill -like pellet. 
 
 Note. — Up to this point the directions for preparing zinc-phosphate for "fill- 
 ing" are the same as for "testing." At this point the pellet should be made 
 oval or elongated for "filling," but should be as spheroidal as possible for "test- 
 ing," the object being to attain a shape which will give the most accurate rebound, 
 
 The second test is, that it roll into pellet with prompt cessa- 
 tion of adhesion to the rolling finger, and that it does not adhere 
 to the finger when it is pressed upon it to determine this. 
 
 Third test. — In one or two minutes, by' the watch, it should 
 glaze and rebound when dropped upon wood, glass, porcelain, 
 or marble, but not necessarily upon metal. 
 
 Fourth test. — In five minutes, it should give a porcelain-like 
 feel and sound when tapped gently on the edges of the lower 
 teeth, and should have no " sticky " feehng when pressed be- 
 tween the fingers. 
 
 * See Appendix, Sec. 5. 
 
ZINC-PHOSPHATE. 169 
 
 Fifth test. — In ten or fifteen minutes it should be resistant 
 wlien taken bet'O'een tlie teetli and bitten upon ; and, if bitten 
 •v\-itli sufficient force, it should IreaJ: with a clean, sharp frac- 
 ture. » 
 
 Sixth test. — In ticenty minutes it should be difficult of punc- 
 ture to the point of the spatula, even "\rith considerable force ; 
 and it should take a fine and -persistent burnish. 
 
 Seventh test. — In thirty minutes it should have no taste, or 
 at most an astringent, metallic taste, like that of chloride of 
 zinc, but not acid. 
 
 It should now be impenetrable to the point of the spatula, 
 even with decided force, and should rebound, with ivory-like 
 elasticity, when dropped from no greater height than an inch. 
 
 I will repeat, that an experience of three years decides me 
 in the opinion that just in proportion as a zinc-phosphate ce- 
 ment responds approximately or accurately to these tests, so 
 does it make, in a majorit}^ of cases, the most durable and the 
 most satisfactory fillings possible to this filling material. 
 
 If an oxy-phosphate or zinc-phosphate is " poor '' or " doubt- 
 ful," it will respond to "testing" as follows: 
 
 First. — It will not require so much force, even when mixed 
 " stiff," to take the mix from the spatula. 
 
 Second. — It Avill adhere to the finger while rolling into pellet, 
 and will be lifted from the palm of the hand by pressing the 
 finger lightly upon it^ 
 
 Third. — In from one to two minutes it will not glaze even 
 though it rebound ; and it ^^"ill, usually, not rebound.^ but will 
 fall " dead " or motionless. 
 
 Fourth. — \nfive minutes it may give porcelain-like feel and 
 sound when tapped gently upon the edges of the lower teeth, 
 but will usually have a "sticky" feeling if taken and pressed 
 betAveen the fingers. 
 
 Fifth. — In ten or fifteen minutes it will not be resistant be- 
 tween the teeth ; but if bitten upon with gentle, sufficient force, 
 will admit of indentation. 
 
 Sixth. — In ticenty minutes it will permit of puncture by the 
 point of the spatula, even with moderate force ; and it Avill not 
 take a persistent burnish, even though it admit of temporary- 
 polish from the burnisher. 
 
170 PLASTICS AND PLASTIC FILLING. 
 
 Seventh. — In thirty minutes it will still liave decided taste, — 
 metallic, astringent, — and sometimes even more than this, de- 
 cidedly acid. It will, even yet, permit of penetration by the 
 point of the spatula, and will cut like plaster of Paris, or, even 
 worse, like zvax. 
 
 One of the most marked tests of zinc-phosphate is the prompt 
 loss of taste on the part of a good material — in an hour or 
 less — and the persistence with which an inferior material will 
 retain the astringent, and even the acid taste, sometimes for 
 days. 
 
 This is attributable to the imperfect combination of the 
 menstruum and powder, which results in a mixture of phos- 
 phoric acid and oxide or nitrate of zinc — with acid reaction — 
 instead of forming the neutral hydraulic cement recognized by 
 plastic dentistry as " ZINC- phosphate." 
 
 DiEECTIONS FOR USING ZiNC-PHOSPHATE. 
 
 It has been noted that the " mixing " of zinc-phosphate is the 
 same for "testing" as it is for use as a filling material, up to 
 the point when the mass is rolled into pellet on the palm of 
 the hand. For filling, this pellet should be made oval or elon- 
 gated, to further its facile introduction to the cavity of decay. 
 
 The pellet should then be taken by a pair of foil-pliers and 
 placed in the prepared cavity. 
 
 The filling should be introduced by appropriate smooth., flat, 
 or round-ended instruments, which may be found in Nos. 2, 3, 
 6, 6, 7, and 8 of the set of amalgam filling instruments. 
 
 The filling should be worked into place, and the condensation 
 of the material effected by pressure of the face 'of the filling in 
 precisely the same manner as is done with soft foil, with the 
 exception that the same smooth-faced instruments should be 
 used instead of pointed or serrated fillers. 
 
 It will be found advantageous to touch the faces of the in- 
 struments to an " oil-pad," — see Gutta-percha, — as this pre- 
 vents adhesion to them of the filling material; particularly 
 is this useful in filling approximal cavities and in " facing " 
 built-up crowns. 
 
 The superfluous portions of the mass — should there be any 
 — ought to be so manipulated as that they will overhang the 
 
ZINC-PHOSPHATE. 171 
 
 edges of the cavity. "Wiien tliis is done, they readily break 
 away, leaving the filling nicely adapted to the walls of the 
 cavity^ and it also secures a smooth^ compressed surface to the 
 filling. 
 
 In filling large, difficult, and, in a measure, inaccessible cavi- 
 ties, it is essential to good results that several mixings should 
 be made, each of the various portions heing introduced separately^ 
 and manipulated just like a pellet of soft foil. 
 
 In cavities between teeth which extend up to, and particu- 
 larly und^r, the gum, it is necessary to fill out to the cervical 
 edge and downward for at least one-third of the cavity with 
 gutta-percha, as a double preventive to decay of the tooth and 
 disintegration of the zinc-phosphate. 
 
 Note. — The disintegration of oxy-chloride of zinc at the cervical portion of 
 the filling has been referred to ; and it will therefore only be necessary to men- 
 tion that zinc-phosphate has the same peculiarity, but in less degree. It is, how- 
 ever, sufficiently vulnerable at that point to render it imperative that a " guard" 
 of gutta-percha or submarine amalgam, according as the tooth is more or less 
 conspicuous, should be first introduced. 
 
 After the introduction of the filling, it should be kept dry 
 for at least fve minutes. It should then be varnished, and the 
 varnish be allowed to dry thoroughly. If it is not easily prac- 
 ticable to maintain the five minutes of dryness, the filling should 
 be varnished immediately upon completion.* 
 
 If any further finishing — for articulation, etc. — is required, 
 the filling should be allowed to harden for at least thirty min- 
 utes — longer time is better, if possible — before this is done ; 
 after ivhich it should again be varnished as before. 
 
 Varnish for this purpose may be made from any of the fol- 
 lowing formulae : 
 
 R Absolute Alcohol f5i. 
 
 Gum-Sandarac ~) 
 
 (selected tears) j * ^^s. xxx. 
 
 A good varnish, but slow dryer. 
 
 B Sulphuric Ether f5i. 
 
 Gum Copal grs. xxx. 
 
 A good varnish and quick dryer, but disagreeably odorous to some. 
 
 * See Appendix, Sec. 6. 
 
172 PLASTICS AND PLASTIC FILLING. 
 
 R Metbylic Alcohol f5i- 
 
 Gum-Sandarac grs. xxx. 
 
 A good varnish, and reasonably quick dryer.* 
 
 In finisTiing "ziDC-pliosphate" fillings, cutting instruments — 
 like No. 9, for example — files, burrs, stones, and disks are ad- 
 missible. When files or burrs are used, tliey should be either 
 perfectly dry or thoroughly wet ; as these conditions, in great 
 degree, prevent them from becoming clogged. 
 
 The face of the filling is better if burnished after it is thor- 
 oughly hardened. For this purpose a steel or agate burnisher 
 can be used. If the face of the filling is marked from using a 
 steel burnisher, it is readily cleaned with pulverized pumice on 
 a soft pine stick. 
 
 it seems proper that a few final directions, or rather sugges- 
 tions^ should be given with a view to completeness rather than 
 importance. 
 
 In taking the "crystals" from the bottle, it is far better 
 that sufficient be scraped up and shaken or turned out into a 
 spoon, than that the contents of the bottle be warmed by placing 
 it in hot water ; as every such heating is eminently detrimental 
 to a good crystal. Ordinary crystals it does not appear to injure 
 much, if any; for they continue to make cement about as at 
 first. 
 " In taking "fluid" from the bottle, it is better to use a small 
 piece of stick dipped into it, as this method is most accurate 
 and economical. A fresh piece of stick should be used for the 
 making of each filling, as the portion of menstruum remaining 
 adherent to it from time to time is liable to hasten markedly 
 the deterioration of most fluids. 
 
 It has been directed that " more than sufficient " powder 
 should be poured out preparatory to mixing the mass. The 
 reason for this is, that even a respectably good zinc-phosphate 
 will " set " so promptly as to require that no time be needlessly 
 lost in its preparation and insertion, which would necessarily 
 be the case if one were obliged to stop and replenish the stock 
 of powder. 
 
 In returning the surplus powder after filling, care is requisite 
 D' 't to return any which has been touched by the fluid. 
 * See Appendix, Sec. 6. 
 
ZINC-PHOSPHATE. 173 
 
 It is sufficient to say that no menstruum, either crystal or 
 fluid, should be used after it ceases to make a cement which 
 will respond to the " tests " for goodness. 
 
 The best method for removing from the fingers such portions 
 of zinc-phosphate as may adhere to them, is by rubbing them, 
 while wet, with the edge of the glass mixing-slab. 
 
 For the removal of adherent material from the slab, the 
 spatula will prove convenient and effective — scraping the slab 
 while holding it in a stream of water. 
 
 \n removing and replacing the corks from both menstruum 
 and powder bottles, it is better to twist them slowly and stead- 
 ily, always to the right, as this will prevent breaking them. 
 
 Conclusions. — In estimating the value of zinc-phosphate ce- 
 ments, I have realized that much discount must be made upon 
 the statements of most of those who manufacture and dispense 
 them. They have already been invested with such names as 
 indicate gradations of obduracy from porcelain to adamant, 
 but I do not think the provings will rank any su.ch appella- 
 tions as appropriate, or, .indeed, as anything but deceptive. 
 
 Zinc-phosphate cannot be regarded as an " insoluble " cement, 
 but must be accepted as "not very soluble" in the fluids of the 
 mouth. It can, however, be graded as much better than oxy- 
 chloride of zinc. 
 
 It can, in no wise, be esteemed as even a moderate approach 
 to the "ideal filling material," for, although it possesses many 
 of the desired attributes, it is, nevertheless, deficient in a suf- 
 ficient number of them to place it entirely without the pale of 
 consideration in this regard. It has not only been suggested, 
 but strongly recommended as a "pulp-capper," and this merely 
 because it does not irritate that organ ; but it must be remem- 
 bered that a material may be non-irritant and yet be eminently 
 capable of pulp devitalization — vide Cadmium; therefore, I 
 have always warned my classes against this use of the material 
 until it has been proven, by careful, patient experimentation, to 
 be worthy of reliance in this particular, and up to this time 
 my own convictions are rather adverse than favorable to its 
 claims. 
 
 It seems to be especially adapted for articulating, approximal 
 —under guarding — and labial cavities \\\ frail, pulpless teeth; 
 
174 PLASTICS AND PLASTIC FILLING. 
 
 or in teetli containing vital pulps, with these thoroughly pro- 
 tected by zinc-sulphate or gutta-percha ; and in such cases it 
 has stood the " oral test " for nearly three years in a remark- 
 ably satisfactory manner /or a zinc plastic. 
 
 I am experimenting with it as a "liner" for frail teeth which 
 are to be filled with amalgam, and thus far it promises well. 
 
 It will now be seen that from the plastic stand-point, while 
 there exists no such use for zinc-phosphate as would warrant 
 any immediate considerable demand, it is, nevertheless, an im- 
 portant and satisfactory adjunct, and one that will meet the re- 
 quirements of certain cases, which, without it, would be almost 
 insurmountable. 
 
 AETICLE XVII. 
 TEMPOBART STOPPING. 
 
 AMATEEIAL for this purpose has been suggested to me, 
 which I deem worthy of especial notice. It is a mixture 
 of red gutta-percha base-plate, white wax, silex, and feldspar. 
 
 In a sand-bath, over a spirit-lamp, place a small glass beaker 
 or other convenient vessel. In this melt two pennyweights of 
 white wax. When this is melted, add to it six pennyweights 
 of gutta-percha base plate, cut into small pieces ; when this is 
 melted, add three pennyweights of finely pulverized silex and 
 three pennyweights of powdered feldspar. Stir all thoroughly 
 together and let the mixture partially cool. When the mass 
 becomes doughy, press it between two plates of glass, first wet- 
 ting them to prevent adhesion. This compound fulfils the re- 
 quirements of a "temporary stopping" more acceptably than 
 an}^ other which I have ever used.* 
 
 * See Appendix, Sec. 7. 
 
TECHNICALITIES. 175 
 
 AETICLE XVIII. 
 TECHNICALITIES. 
 
 AS in tlie progress of tlie development of plastic-filling ma- 
 terials, instruments for manipulation, apparatus for testing 
 and experimentation, and metliods for utilization have been de- 
 vised, and substances — metallic, organic, and inorganic — have 
 been brought into service, so has it been found needful to coin 
 a technical phraseology by which explanations could be made ; 
 comparison of views be indulged in ; methods referred to ; and 
 advantages and disadvantages of operations be discussed, con- 
 cisely, definitely, and intelligibly. 
 
 So strangely apathetic have been the reputed leaders in den- 
 tistry, that, notwithstanding the constant reference to these 
 terms which has necessarily been made in practice, as repeated 
 demonstration of power to cope with things impossible of ac- 
 complishment by any previous materials and methods has been 
 given, and although attention has been directed to them by 
 public and careful enunciation, they have, up to this present, 
 remained terms possessed of meaning to but few, and these, 
 with rare exceptions, from among the younger and rising mem- 
 bers of our profession. 
 
 It is noted in journal communications that an occasional use 
 of plastic phraseology is indicative of commencing acceptation, 
 and it is now, beyond question, a matter of immediate import 
 that those who purpose saving the teeth of the coming generation, 
 should familiarize themselves with the technicalities of that 
 practice which alone has demonstrated a reasonable capability 
 for the attainment of this, much to be desired, result. 
 
 Ageing. — This term is applied to certain changes which 
 occur to almost every variety of every plastic-filling material. 
 It is also used to express the attainment, by any means, of re- 
 sults which are given by time, either desirable or undesirable ; 
 as, for instance, the "ageing" of gutta-percha is recognized 
 as detrimental, in that the material becomes brash, losing its 
 toughness; it becomes easily disintegrated by attrition and 
 by the fluids of the mouth ; it is crumbly — indisposed to co- 
 here ; it is " time- rotted." Oxy-chloride of zinc powder loses 
 
176 PLASTICS AND PLASTIC FILLING. 
 
 its sharpness of response in setting and also its density and 
 hardness, becoming slow-setting, porous, and soft. 
 
 • The fluids and syrups of oxy-phosphates, and the fluids, 
 syrups, pastes, and crystals of zinc-phosphates, as a rule, lose 
 their value entirely from "ageing," and those which do not, 
 have equally, as a rule, but modified value at any time when 
 compared with an " excellent " menstruum. 
 
 Amalgam alloys, on the contrary, after being cut or filed, 
 improve notably from " ageing." Amalgams made from really 
 good alloys are, without exception, very much better after 
 these have been filed, up for several months. Ordinary alloys 
 work better when "aged" than they do when "fresh," but the 
 better the alloy the more marked is the improvement dae to 
 " ageing." They work much more smoothly, require less mer- 
 cury, set more slowly and yet witja sufficient celerity, and, under 
 every " test," become more desirable. 
 
 Eeference has been made to the fact that, in considerable 
 degree, this effect of time upon cut or filed alloy may be pro- 
 duced by continued attrition of particles, or by repeated ex- 
 posure of particles to the air, or, most probably, by a combina- 
 tion of both. This is done by placing the filings in a cylinder 
 of glass, and causing it to revolve with moderate speed for the 
 space of several hours, and the process is called " ageing the 
 filings."* 
 
 - Bulging. — By this is meant a change of shape which takes 
 place in amalgam, and by which the form of a filling is so 
 altered, from spheroiding, as to present a modified convexity 
 of face. This result is attributed to the spheroidal control of 
 the mercury, and is more pronounced as the metals of which 
 the alloy is composed are more yielding in texture, less obdurate 
 in melting, and more deliberate in cooling. The concomitant 
 of bulging is crevicing^ as, in the attainment of a spheroidal 
 form, the filling material is, necessarily, drawn from such cav- 
 ity-edges as have had to be left straight instead of curved — 
 concave. 
 
 This terra is also applied to the softening and swelling out 
 which sometimes, though very rarely, occurs in fillings of gutta- 
 percha — notably red gutta-perclia, or iase-jylate. Tliis result is 
 generally attributed to inferiority of material ; but, though 
 * See Appendix, Sec, 1. 
 
TECHNICALITIES. IfT 
 
 tMs may "be usually a correct ascribing, I am incliA^tf k> the 
 opinion fliat, in some mouths, it will occur with ^he v- .ry best 
 gutta-percha. 
 
 f Buffering. — This word is used to denote at» opefa,tion by 
 means of which a yielding material, like gutt-^.-percha, is pro- 
 tected from attrition by a more or less resisiant material, like 
 zinc-phosphate or amalgam. It signifies projection from blows 
 or frictional impinging, and is the method Ajj Avhich the plastic- 
 filler is enabled to utilize the tooth-saving power of gutta- 
 percha in frail bicuspids and molars ir. which are cavities of 
 decay extending up to and under the gum, and opening through 
 upon the articulating faces of the teeth. The " buffer " is gen- 
 erally trunnioned either in dentine or zinc-chloride, though 
 sometimes an acceptable retaining shape can be given to the 
 articulating cavity-edge. 
 
 Capping. — As used with reference to filling^ this word implies 
 completely outside work, in contradistinction to the completely 
 inside work of pulp-capping. W hereas, the latter is done with 
 the softest and most yielding materials used in plastic dentistry, 
 the former is done only with those possessing markedly the 
 characteristic of resistance to attrition. It is used to express 
 the thin covering of a yielding material with which a "tap" 
 for future "venting" may be filled. This is usually gutta- 
 percha, a material which must be protected if the "tap" has 
 to be made upon any surface exposed to attrition. The capping 
 is done either with zinc-phosphate or amalgam, and if with the 
 latter, "facing" amalgam is usually employed, as, by its marked 
 retention of color, the position of the " tap " is indicated. 
 
 Cold- Soldering. — This phrase is used to express one of the 
 most useful possibilities in connection with plastic filling. It 
 is a property of amalgam, that additions of this material can he 
 secured firmly and homogeneously to either gold or amalgam fill- 
 ings, whether they he old or of recent introduction. In this way 
 old fillings are joined on to and made subservient for retaining 
 purposes, in cases of new decay — shallow cavities — encroaching 
 upon or approaching near to such fillings. Large reparations 
 are made with perfect facility in cases where masses of tooth- 
 structure have been broken away from heavily-filled teeth. 
 Fillings are made to present the appearance of, and to be, prac- 
 12 
 
178 PLASTICS AND PLASTIC FILLING. 
 
 ticall}^, one large filling, by merely removing the carious tissue 
 from between them and joining them with new filling material 
 — amalgam. 
 
 Pins for pivoting are fixed in position by drilling oval drill- 
 holes in amalgam root-fillings, and securing the pins with freshly- 
 made amalgam. 
 
 Gold bands are held firmly upon crownless roots by filling 
 the canals with amalgam and cold -soldering the bands by 
 building up amalgam crowns within them. 
 
 Linings of amalgam are placed in cavities of doubtful teeth, 
 which are thus secured against decay, and, after many days, if 
 results are unfavorable, this thin stratum of filling is readily 
 removed. If, on the contrary, the result is favorable, the re- 
 maining portion of filling is just as readily added on. 
 
 Crowns are partially built up, and if circumstances — such 
 as want of time for completion of operation ; urgent demand 
 for services by other patients, etc., — compel cessation of work, 
 it is a matter of no moment so far as any complication is con- 
 cerned, for, at any time, the work may be resumed just as if 
 it had not been interrupted. All these, and many other re- 
 quirements equally convenient to meet and desirable to avail 
 one's self of, are boons bestowed alike upon patient and opera- 
 tor by " cold-soldering." 
 
 As in all soldering the face of the metal to be soldered upon 
 must be made bright either by scraping with an excavator, 
 smoothing with a file, or cutting with a burr-drill; a small 
 portion of amalgam is then mixed very soft^ and, being placed 
 upon the brightened surface, is rubbed over it until it is thor- 
 oughly " amalgamated," after which all superfluous amalgam 
 should be removed. Having thus obtained a soldering surface, 
 the appropriate amalgam — indicated by the position of the 
 cavity or the exigencies of the case — should be mixed as usual, 
 and the filling made. The necessary caution in regard to care 
 in using, if such is required, should not be forgotten, and, with 
 such admonition, the patient can be assured that upon the com- 
 plete hardening of the filling material a result will have been 
 attained which, in strength, durability, and homogeneity, will 
 be precisely the same as though the filling had been originally 
 made with its present contour and dimensions. 
 
TECHNICALITIES. 179 
 
 Grevicuig. — This word is used to express that result referred 
 to under " bulging," when an amalgam filling has assumed such 
 shape, from tendency to spheroid, as to have drawn from the 
 margins of the cavity. It is probable that more amalgam fill- 
 ings have been unjustly condemned, as worthless, from this 
 " crevicing " than from any other cause. So far from being a 
 serioQS and irremediable defect, it is most frequently yqtj easily 
 and quickly removed, and, by its removal, a filling of great 
 value is secured. 
 
 The removal is effected either by filing, stoning, or burring 
 off the superfluous amalgam ; and a filling is thus again brought 
 into contour with the cavity edges, which, having bulged in 
 one direction — outwardly — has likewise, from the same cause, 
 become even more accurately than ever in apposition with the 
 cavity walls. Besides this, the filling is usually an old one, or, 
 at least, one of several years' duration, and, during all the time, 
 a formation of sulphides has been progressing, which, by im- 
 pregnation of contiguous dentine, has rendered that tissue of 
 most congenial potentiality with the surface of the filling. All 
 this harmonious condition of things has been reached by that 
 gentle gradation of change which the experience of many years 
 proves to be productive of extraordinary permanency. 
 
 It may, therefore, well be questioned as to whether the re- 
 moval of such fillings is not alone of doubtful benefit ; but, far 
 more than this, acts of positive wrong to patients — work which 
 it behooves every conscientious practitioner to weigh well be- 
 fore continuing in the stereotyped condemnation based upon 
 convictions which time has shown to have been founded upon 
 prejudice alone. 
 
 If crevicing is of such depth as to render the removal of a 
 superficial stratum of anialg^am insufficient to restore to the 
 filling a desirable perfection, it is proper that a groove or canal 
 should be cut, with an oval burr or fissure-drill, throughout- 
 the length of the crevice. This groove should then be filled 
 with freshly made amalgam, which, as has been stated, will 
 unite homogeneously with the former filling. 
 
 It is frequently possible, at the present time, to very much 
 improve the appearance of these creviced amalgam fillings by 
 cutting out a thin stratum of the old amalgam, and replacing 
 
180 PI.ASTICS AiS"D PLASTIC FILLING. 
 
 it "W'itli one of tlie good color keepers, either " contour " or 
 " contour " and " facing," half and half, or even, in rare cases, 
 where edge-strength is of no special consideration, with "facing" 
 amalgam alone. 
 
 Domeing. — This operation consists in building up a pointed 
 or conical dome of gutta-percha from the pulp-cavity towards 
 that portion of the periphery of a filling at which it would be 
 proper to "tap" if crown-tissue were existent. Having thus 
 formed this " dome," the filling, of amalgam, is made, and the 
 point of the dome covered in. If at any future time it becomes 
 advisable to enter canals, the entrance is easily made by drilling 
 through the thin covering of amalgam, and removing the gutta- 
 percha by means of a warmed instrument or small oval burr. 
 The entrance having been effected, and the desired relief hav- 
 ing been given, the matrix left by the removal of the dome is 
 readily refilled, and the position of the tap made perfectly ap- 
 parent by capping with facing amalgam. 
 
 For superior molars, the dome should point towards the centre 
 of the articulating faces ; for inferior molars, the dome should 
 point mesio -huccally. Molars are the only teeth which it is 
 ever necessary to dome. 
 
 Facing. — In " facing," we have the aesthetic of plastic den- 
 tistry. It is, in the direction of beauty, that which cold- 
 soldering is in the direction of utility. Facing is done with 
 gutta-percha, zinc-phosphate, and amalgam ; the incisors and 
 cuspids either with gutta-percha or zinc-j)hosphate, the bicus- 
 pids and molars usually with amalgam, exceptionally with 
 gutta-percha. 
 
 Facing is of two grades, — the facing of fillings and the facing 
 of "built-up" teeth. The first is of comparatively circum- 
 scribed extent, and is done in cases where decay has progressed 
 in such manner as to impinge upon the labial faces of incisors 
 and cuspids. Cavities in these teeth having been properly 
 lined, if necessary, and filled in contour with contour amalgam, 
 the filling is allowed to harden for about thirty minutes, after 
 which it is cut into with the trimmer from the front. The ex- 
 cavation is bounded by the remaining labial enamel on the one 
 side and by the contour-line of the filling on the other. The 
 Blot thus cut out is, in this way, made of the exact shape of the 
 
TECHNICALITIES. 181 
 
 missing portion of enamel, and the slotted filling is then allowed 
 to harden thoroughly — an hour or more, 
 
 If it is desirable to avoid retaining the patient longer at this 
 sitting, the slot may be filled temporarily with low-heat gutta- 
 percha. This is not sufficiently resistant to endanger the frail, 
 bevelled edges of the newly-made amalgam on the contour edge. 
 The slot should be finally filled either with facing gutta-percha 
 (gutta-percha, 1 part ; oxide of zinc, 6|- or 7 parts) or with zinc- 
 phosphate, by making the shade desirable. Both gutta-percha 
 and zinc-phosphate may be shaded yellowish by the addition of 
 a little chrome-yellow, and bluish by the addition of a very little 
 lamp-black. 
 
 These gutta-percha facings can readily be made to match the 
 color of the teeth so closely as not to attract the least attention. 
 They are quite durable, lasting frequently for several years, 
 and are renewed at any time, if required, in a few minutes. 
 
 The zinc-phosphate facings are, as j^et, more experimental, but 
 I have a goodly number which, during the past three years, have 
 proven eminently satisfactory, I never use a zinc-phosphate 
 for facing imless it responds well to all the tests given for 
 " good " material, and I am very careful to maintain dryness 
 during filling and setting^ — usually with rubber-dam, — and to 
 varnish thoroughly, and to let the varnish dry completely. 
 
 In facing "built-up" crowns, it is first essential that the crown 
 be built perfectly with contour amalgam. In no other way can 
 the contour-lines for facing be attained with any degree of accu- 
 racy or beauty. In the first building the whole anatomy and 
 expression of the crown can be given, and the proper articula- 
 tion is secured. The result is a crown which, for size, appear- 
 ance, strength, and utility, would be all that could be desired ; 
 but the insuperable objection to such a crown is, that it will 
 probably change to a color worse even than that of gold. To 
 obviate this, the buccal face of the crown is concaved most 
 delicatety, most accurately, and artistically. This is no easy 
 task ; for the slightest slip of the trimmer or excavator, and, 
 above all, the least 'inal a propos whirl of the burr-drill, will 
 mar the beauty of the contour-lines. 
 
 The concavit}" being made, if it is to be filled with facing 
 amalgam, — tin, silver, gold, and zinc, — the work can be well 
 
182 PLASTICS ANJ) PLASTIC FILLING. 
 
 done immediately, and, for a vast majority of cases, T prefer 
 this facing to any other, as the built-up crowns appertain, 
 almost exclusively, to bicuspids and molars^ which, with such 
 facings, almost always make very presentable and, indeed, 
 pretty operations. 
 
 But it is nevertheless true that, occasionally^ facing amalgam 
 will discolor, and it is for this reason that we sometimes have 
 to resort to the gutta-percha and zinc-phosphate facings for 
 bicuspids. When this is so, the concavities should be made 
 fnuch deeper then is needed for the using of amalgam, and me- 
 chanical retahiing-slots, grooves, or undercuts should be made 
 for the securing of the facing. 
 
 In these cases gutta-percha has made a good record, usually 
 doing service for from two to five years, and then requiring but 
 a thin film of additional facing. 
 
 Much thought, labor, and experimentation have been bestowed 
 upon the accomplishment of this desideratum in plastic work, 
 and the results have been such as to cause the plastic-fillers to 
 feel well compensated for all their toil. 
 
 But the satisfaction of the workers has been a slight thing 
 in comparison with the outpourings of delight and gratitude 
 which have come from patients, especially lady patients, who 
 have seen their frail but beautiful " pearls " crumble away from 
 "the jewels of gold," until, while yet in young life, they had 
 come to smile smiles of barbaric magnificence as the "ruby 
 portals " revealed a terrible preponderance of the brilliant tri- 
 umphs of " first-class " dentistry. 
 
 These are the dentures which, taken after the dropping out 
 of the third or fourth line of such work, after the expenditure 
 of dollars by the hundred until the hundreds had wellnigh 
 reached a thousand^ after the remnants had come to be a 
 jagged row of roots and broken cusps and edges, have been so 
 " built up " and " faced " as to have in such degree restored the 
 original beauty of expression to their possessors, that words 
 seemed inadequate to do their feelings justice, and written 
 praises have blessed the day on which they learned of plastic 
 dentistry. 
 
 Frotting. — This term is from the French, " frotter," and sig- 
 nifies " to rub." It is applied to the method by which certain 
 
TECHNICALITIES. 18& 
 
 kinds of plastic materials are tested for " probable wear.'' 
 These are oxy-clilorides, oxj-phospbates, and zinc-pliospbates. 
 The illustration of the machine for "frotting" will give so 
 clear an idea of its working as to need no description, and it 
 will therefore suffice for me to say that pellets of the materials 
 to be tested are made into pill form and placed in a small tube 
 containing water, slightly acid, slightly alkaline, or neutral, 
 and are then frotted by the pendulum-like motion given to 
 . the tube by wheels arranged like clock-works and driven by 
 a powerful spring. 
 
 In this manner the relative durability of such plastics as 
 disintegrate in the fluids of the mouth is quickly tested, and 
 quite a number of materials, which, from the enthusiastic and 
 emphatic assertions of their makers, would have given rise to 
 costly and tedious lines of disappointing experimentation, have 
 been strangled almost at their birth. 
 
 Guarding. — For many years it has been noted that fillings 
 are prone to fail at the cervical edge. So frequently is this the 
 case, that this part of the cavity wall has come to be known 
 as " the vulnerable spot." In foil practice, this failure has ever 
 been attributed to "defective manipulation;" but this reasoning 
 has always been a matter for peculiar comment upon the part 
 of the plastic-fillers, and the explanation has been regarded by 
 them as not at all satisfactory. They have thought it strange 
 that the easiest part of the foil-filler's work — the introduction 
 of the foundation or first pieces — should, have been so uni- 
 versally badly done. They have thought that, of all the fill- 
 ing, the cervical portion would be the best, and that, in conse- 
 quence, it should the least permit recurrence of decay. They 
 have noted the same unsatisfactory results at the cervical mar- 
 gins of cavities filled with plastic fillings, and they could not 
 ascribe these failures to " defective manipulation ; " for they 
 knew the manipulation of the filling material at this point was 
 as perfect as it possibly could be. They knew that there was 
 no " loosening of the first pieces ; " no " slipping of the first 
 layer; " no "leakage from turning; '' no "crumbling of cavity 
 walls from malleting ; " and yet they knew that the vulnerable 
 spot existed for them just the same as it did for the "defective 
 manipulators." 
 
184 PLASTICS AND PLASTIC FILLING. 
 
 It lias also been observed tliat by far tlie most frequent and 
 most extensive cavities of recurring decay are found in con- 
 nection with gold-fillings; tliat second in relative proportion, 
 numerically, tlie cervical edge of cavities is vulnerable under 
 tin and silver amalgams ; that it is vulnerable in third degree 
 under fillings of tin-foil, or of silver, tin, and copper amalgams ; 
 that it is still less vulnerable — in fourth degree — under gutta- 
 percha fillings; and that here the grades of vulnerability of 
 cervical tooth-bone cease. 
 
 And now, it has been noted that, although recurrence of cav- 
 ity formation continues, it does so at the expense of filling 
 materials instead of tooth-bone. The fillings of oxy-chloride 
 of zinc, oxy-phosphate of zinc, and of zinc-phosphate, in the 
 order given, disintegrate at their cervical margins; the first, 
 notably; the second quite promptly, and the third, though 
 much more durable, far too quickly. 
 
 To the mind of a plastic-filler the " defective manipulation " 
 theory offers no explanation whatever of all this; but with the 
 Palmer theory of relative consonance of potential, or "compat- 
 ibility between filling material and tooth-bone," everything 
 seems clear and easy of explanation. 
 
 It is understood, by consent, that all substances have a defi- 
 nite molecular motion which is expressed by the word " poten- 
 tial." It is proven by galvanometric experiments that contact 
 between almost any two substances — using the word in its 
 general sense — "develops electrical phenomena. 
 
 It is agreed that needle deflection denotes difference in po- 
 tential between substances just in proportion to the magnitude 
 of the deflection. 
 
 It is agreed that in proportion to difference in potential so will 
 contact of substances produce electrical and chemical results. 
 
 It is agreed that one of the substances becomes positive to 
 the other, and that the other becomes negative to the first. 
 
 It is agreed that, under the action excited by contact, the 
 substance which is proven to be positive is markedly disinte- 
 grated^ and it is inversely deduced that disintegration of sub- 
 stance proves positivity to that substance. 
 
 It Im agreed that moisture increases most notably the rapid 
 ity aod extent of this disintegration ; and, that moisture pos 
 
TECHNICALITIES. 185 
 
 sessed of .certain cliaracteristics which render it neutral — as it 
 is termed — least facilitates this action; while moisture pos- 
 sessed of other characteristics — acidity, alkalinity, etc., — most 
 promotes it. 
 
 Thus far all is clearly scientific, and the plastic-fillers accept 
 this as a hasis upon which to ofl'er an explanation. 
 
 They find aid in this matter from observation of filling ma- 
 terials in their relation to the tables of " conductivity ;" from 
 their relative possession of the characteristic of " liability to 
 tarnish," — formation of more or less soluble salts ; from their 
 possession of physical integrity, or, liability to disintegration 
 by chemical action ; and from their relative capability for easy, 
 and consequently more perfect, adaptation to cavity walls. 
 
 All these considerations afford subject-matter for thought to 
 the plastic-filler, while the gold-filler, having but one material 
 to think upon, can think of but one thing as promising success, 
 viz., perfection in manipulation ; and but one reason can present 
 itself to his mind as explanatory of failure, which is " defective 
 manipulation," 
 
 With thought upon the points which I have presented, there 
 has come an inquiry into the varied characteristics of all the 
 plastic materials that are subservient to the saving of teeth ; a 
 systematic investigation of their behavior under all possible 
 conditions, and in all possible positions, in the mouth ; a prac- 
 tical testing of the harmonious and inharmonious relations ex- 
 isting between theory and experiment ; and it is with peculiar 
 satisfaction that I am able to assert the singular harmony be- 
 tween theory and practice which has been proven to exist by 
 the tabulated work of the past twenty years. 
 
 So happily successful has been the meeting of indications by 
 means based upon the principles of the " compatibility " theory, 
 that the most desperate cases, in the way of large numbers of 
 dreadfully inaccessible cavities filled with the most sensitive 
 tissue, and in teeth of the softest and frailest structure, are re- 
 garded by the educated plastic-fillers with perfect equanimity, 
 and are so treated and filled as to prove eminently satisfactory 
 alike to patient and operator. 
 
 Among the most convincing proofs of the correctness of the 
 theory upon which the plastic-fillers base their choice of ma- 
 
186 PLASTICS AND PLASTIC FILLING-. 
 
 terial for saving teetH, is tlie operation under discussion, known 
 as " guarding." 
 
 " Gruarding " is the placing of a material in apposition witli 
 the cervical wall of a cavity of decay, which shall, by its pos- 
 session of certain physical characteristics, act under certain 
 "law" to prevent, in greatest degree, the recurrence of decay 
 at that " vulnerable spot." 
 
 It is to the plastic-fillers of the present day that dentistry is 
 indebted for the utilization of tin-foil as a guard at this point. 
 It is true that tin-foil has long been used by the most promi- 
 nent gold-fillers as a means for the " better saving " of soft 
 teeth, but its advocacy is found, hy reference to the record^ to be 
 based upon the greater softness of the material, and its conse- 
 quent easier and more perfect adaptation to the cavity walls. 
 
 Thus it will be seen that the manipulative idea was ever so 
 prominent as to be the only thing thought worthy of attention. 
 
 The further proof that this is so may be found in the con- 
 stant repetition, upon scores of occasions, that this soft mate- 
 rial was only intended to subserve a temporary purpose ; for it 
 is everywhere, and at all times, agreed that such fillings were 
 to be allowed to remain only until" the teeth become thoroughly 
 calcified, when they were to he removed and peemanent fillings 
 of GOLD were to he introduced! 
 
 The gold work upon soft teeth has been founded on this prin- 
 ■ ciple, and has been practised under this teaching for the past 
 fifty years, and I regard it as unnecessary that I should waste 
 one word in reference to its record. 
 
 It is now more than twenty years since I commenced the use 
 of tin-foil, amalgam, and gutta-percha as guard-fillings at the 
 cervical walls ; not because they were soft and could be more 
 perfectly adapted to the parietes, but, EMPIRICALLY, because I 
 had noted that fillings made from these materials permitted 
 occurrence of decay less promptly than did gold, even when 
 worked by the best manipulators of that day ; not with the 
 avowed intention of removing them when the tooth -structure 
 became thoroughly calcified, but with- the intention of renew- 
 ing them when drfcay should eventually recur, which I knew 
 would pr(jbably be the case at some future time, even though 
 the recurrence should be much retarded. 
 
TECHNICALITIES. 187 
 
 This, whicli at tliat time was empiricism^ lias become, by the 
 adoption of the Palmer theory, the strictest following of science. 
 Guarding by gutta-percha or amalgam is now done with full 
 reference to the known requirements, the physical capabili- 
 ties for response to these upon the part of the filling ma- 
 terial, and a knowledge of future probabilities based upon 
 definite data which, in turn, rest upon definite, acknowledged 
 "law." 
 
 In cavities which are accessible, in which dryness can be 
 attained and maintained, in which lining with oxy-chloride and 
 final filling with either a single or a combination amalgam is 
 thought to be the proper practice, a guard' o^ gutta-percha is 
 the thing indicated. This should be made as thin as possible 
 consistent with certainty that it thoroughly protects the cervi- 
 cal edge. It may be given bulk in moderate degree within the 
 cavity, and worked to a feather-edge at the cervical margin. 
 It is better that it protrude a little, so that the lining and final 
 filling having been accomplished, and the amalgam having suf- 
 ficiently set, the " guard " may be neatly trimmed off with a 
 heated instrument. This insures nice adaptation, desirable 
 finish, and perfect protection. 
 
 In cavities w.hich are inaccessible and which run under the 
 gum, and in which it would be impossible to maintain dryness 
 except by very inflictive methods, — dams, dam-clamps, or dam- 
 ligatures, — it is far better to trust to submarine amalgam. This 
 should be mixed reasonably plastic, sufficiently so for perfectly 
 easy manipulation, and, having attained what dryne'ss may be 
 possible, it should be carefully tapped into complete apposition, 
 with the wall. It should then be wafered, that firmer consist- 
 ence may be given the material. It should be built up de- 
 cidedly thicker than a guard of gutta-percha, that, when set, it 
 may be trimmed in such fashion as to leave a nech portion^ which 
 may be utilized, if desired, for the maintenance of dryness, by 
 rubber-dam, during the further lining or filling of the remain- 
 ing portion of the cavity. 
 
 When fillings of gold fail at these "vulnerable spots," guard- 
 ing with plastics is a very comfortable and satisfactory method 
 of repairing damages. The guarding, even in this compara- 
 tively inaccessible position, — a work which, with gold, would 
 
188 PLASTICS AND PLASTIC FILLIIn'G-. 
 
 be increasedlj difficult and painfal, — is almost invariably less 
 painful, less tedious, less expensive, and more permanent than 
 was tlie original operation. 
 
 When fillings of gutta-percha fail at cervical edges, they 
 may readily be repaired either by adding gutta-percha, which 
 is done by first softening the edge of the original filling by 
 heated instruments and then joining the required amount of 
 material to it, or by grooving the cervical margin and filling 
 with submarine amalgam. 
 
 If amalgam fillings fail at cervical edges, it is only needed, 
 after the required excavating, that a guard of " submarine " 
 shall be cold-soldered to the old filling. 
 
 As conclusion to " guarding," I would say that the plastic 
 school of dentistry holds to the view that the "vulnerable 
 spot " is found to be located at the cervical edge, not from any 
 unusual or insurmountable difficulty which precludes the possi- 
 bility of perfect manipulation of material at this point, but be- 
 cause in all cases, and particularly in soft-tissued teeth contain- 
 ing vital pulps, moisture is here soonest, most constantly, and 
 most abundantly brought in contact with the filling material. 
 It holds that this moisture is not alone that from the outside, 
 and which by leakage — as this term is generally understood — 
 might notably aid " defective manipulation " in its work of 
 destruction ; but that it is also that from the inside, the fluid 
 which is essential to the maintenance of vitality, and which is 
 thus ever present in living tissue. 
 
 It holds that, as this moisture is gradually brought into con- 
 tact with filling material, a degree of electro-chemical disinte- 
 gration of the positive substance occurs, which, in rapidity and 
 extent, is in direct ratio with the existing difference in poten- 
 tial between the two substances in contact. 
 
 It holds that the difference in potential between gold and 
 tooth -bone is proven to be very great, and the positivity of 
 tooth-bone to gold is equally proven, by the rapid recurrence 
 of decay at this cervical margin, when cavities in teeth of 
 markedly soft structure are filled with gold. 
 
 It holds that the lessening difference in potential between 
 amalgam and tooth-bone and gutta-percha and tooth-bone is 
 proven by that comparative immunity from decay which, in 
 
TECHNICALITIES. 18& 
 
 direct ratio, is found to result when cavities in soft teetk are 
 filled with, or guarded by, these materials. 
 
 It holds that the negativity of tooth-bone to filling material 
 is proven by the disintegration of the fillings made with zinc 
 plastics ; and thus, while it concedes to these plastics a tooth- 
 saving power, in a certain sense, it nevertheless denies to them 
 the ability to perform " guard " duty. 
 
 Heating. — This term is applied to various processes and re- 
 sults ; but its exact signification in any given case is under- 
 stood from the connections in which it is used; thus the "heat- 
 ing" of gutta-percha refers to its softening preparatory to using 
 it for filling, and is understood to be a process which inust be 
 done over water for all such gutta-perchas as require less than 
 210° F. for proper softening ; and equally must be done, and 
 with great care, upon metal plates subjected to the direct flame 
 of gas or the spirit-lamp if " high heat " gutta-percha is to be 
 emploj^ed. 
 
 The " heating " of instruments is understood to refer to the 
 preparing of these for the insertion or finishing of gutta-per- 
 cha fillings of medium or high-heat grades, a process which is 
 accomplished by a tool-heater or, less conveniently, by heating 
 them in the flame of a spirit-lamp. 
 
 The " heating " of gutta-percha for testing its grade, and its 
 relative quality as pertaining to any given grade, is a process 
 which is conducted on a gutta-percha tester, and which gives 
 the exact thermometric grading of different samples of this 
 filling material. 
 
 The " heating " of zinc-phosphate menstruum refers to the 
 melting of the crystals, a process which requires much care 
 that it be done without permitting the boiling of the syrupy 
 fluid which results. This "heating" is done upon a small 
 spoon of platinum or silver, which is held high up over the 
 flame of a spirit-lamp, that the melting may be done gradually, 
 and may be kept perfectly under control. 
 
 The " heating " of a zinc-phosphate mix is that generation 
 of heat which always accompanies the union of the menstruum 
 and powder. It is of very varied intensity and duration ; but 
 if of decided intensity, — sometimes sufficient to burn, — or of 
 decided length of duration, it is a fair indication of question- 
 
190 PLASTICS AND PLASTIC FILLING. 
 
 aHe material. Tlie heating of a good zinc-pliospliate, though 
 perceptible, is neither intense nor of long duration. 
 
 Lining. — This operation, as its name implies, consists in 
 covering the inner surface of cavity walls with a thin stratum 
 of material which shall subserve the purpose either of pre- 
 venting recurrence of decay ; or of affording support to un- 
 yielding filling material which would otherwise rest upon an 
 unsubstantial foundation; or of preventing discoloration from 
 filling materials liable to tarnish ; or of precluding the possibil- 
 ity of clouding from leakage; or of strengthening frail cavity 
 walls. 
 
 The materials used for lining are varnishes made from sanda- 
 rac, copal, inspissated Canada balsam, mastic, etc., facing amal- 
 gam, oxy-chloride of zinc, zinc-phosphate, and gutta-percha, 
 either in solution or as employed for filling.* 
 
 Linings of varnish, facing amalgam, and the zinc plastics, par- 
 ticularly the zinc-chloride, I can heartily recommend, as I have 
 used them very frequently, and for many years ; but the linings 
 of gutta-percha I can only caution against as unreliable. The 
 solutions of gutta-percha have a worse record even than the thin 
 linings of gutta-percha stopping, and this is needless, for a gutta- 
 percha foundation has ever proven insecure in the extreme. 
 
 Linings of varnish are indicated in shallow cavities where 
 only limited undercuts or retaining-holds can be obtained. 
 They should be permitted to dry thoroughly, and will then be 
 found preservative of tooth-bone and preventive of discolora- 
 tion. R. Gum-Sandarac, grs. iij to v; alcohol, fsi.f 
 
 Linings of fiacing amalgam are indicated where contour 
 amalgam is to be used for building portions of crowns on to 
 remaining portions of tooth-tissue which afford but slight an- 
 chorage for the filling. In these cases no space can be given 
 to zinc-plastics, and indeed even the thin space occupied by a 
 coating of varnish, is better utilized by an equal thickness of 
 filling material to which attachment may be made for the con- 
 touring. Facing amalgam meets this requirement. 
 
 Linings of oxy-chloride are the " regular thing." In all 
 cases of deep undercutting; in all cases of frail, thin walls; 
 in all cases of poor tooth-structure ; in all cases of discolored 
 
 *See Appendix, Sec. 5. f Every cavity which can be kept j3er/ec% dry 
 should, on general principles, be varnish lined, at least. 
 
TECHNICALITIES. 191 
 
 teeth ; in all cases of marked tendency to recurrence of decay, 
 I can advise a good oxy-chloride lining. 
 
 Linings of zinc-phosphate are yet regarded as experimental. 
 There are certain qualities pertaining to this material which 
 render it more desirable, as a liner, than zinc-chloride. These 
 are its waxy ductility in working, which permits its placing 
 by means of burnishers instead of by pelleting ; its perfect 
 adaptation to cavity walls in such manner as to be easily and 
 nicely brought to feathei'-edges at cavity margins ; the rea- 
 sonable strength of such edges when compared with oxy- 
 chlorides; the greater celerity with which it hardens, and its 
 valuable characteristic of non-shrinkage. 
 
 All these give to zinc-phosphate advantages which it be- 
 hooves us to utilize, and it is therefore eminently proper that 
 experimental knowledge as to its maintenance of integrity and 
 permanence of utility shall be obtained as promptly and as posi- 
 tively as is compatible with safety to such teeth as require such 
 aid. 
 
 Mixing. — By this is meant the final uniting of two prepara- 
 tions, both of which^ at the present time, are compounds^ which 
 mixture results in a material which is either directly used for 
 some process connected with the filling of a cavity, or is to be 
 utilized for this purpose by some other process, as " mixing " 
 alloys for making another alloy. 
 
 The " mixing " of such compounds, as, by this process, make 
 materials for capping pulps, lining cavities, or filling teeth, is 
 always best done upon a glass-slab with a spatula. The methods 
 of the various mixings of this kind have been given, in place, 
 under "oxy-chloride," " oxy-sulphate," and "zinc-phosphate;" 
 but it remains for me to say that in the making of these mix- 
 ings there is the greatest possible individual difference. 
 
 From this fact it is impossible that all should attain results 
 which shall be alike valuable or satisfactory, and it is to this, 
 that many of the deficiencies ascribed to plastic materials are 
 due. Every operator thinks that he can mix any plastic with 
 perfect facility, whereas, the truth is that not one in an hundred 
 can make the most advantageous "mix" with any of them. 
 They are either mixed too thin or too thick ; too slowly or too 
 quickly; the menstraam is either overloaded or undercharged; 
 
192 PLASTICS AND PLASTIC FILLING. 
 
 the mix is taken for use either before tlie proper time, or when 
 the setting has advanced so far as that it is interfered with, and 
 the material rendered practically valueless in its introducing. 
 
 Note. — Some time since, I was requested by a manufacturer to tell him what 
 I thought of a material which was on his office-table. I poured out upon a slab 
 a little of the fluid and a portion of powder, and after making the mix, and not- 
 ing its behavior, told him it was a good oxy-chloride. " Do you think it good? " 
 said he. " Certainly, quite so," I replied. Upon this he showed me a letter 
 with which the package had been returned ; in it the material was stamped as 
 perfectly worthless, and a very emphatic request made that no more of that 
 kind should ever be sent again. After some weeks, the gentleman — who is an 
 expert at mixing — told me that he had kept the material in his office until he 
 had requested quite a number of visiting dentists to manipulate it, and said he, 
 " not one made what I should call a decent mix." 
 
 I could readily appreciate this, for my own office has been 
 the scene of numerous very funny "mixes" at the hands of 
 some very "eminent" practitioners; and it is from this want 
 of knowledge that some of the most miserable plastics have 
 secured "testimonials" which will in the near future be as 
 "peculiar" as are zinc alloys, but not nearly so satisfactory . 
 
 Such "mix" easily ; they require no knowledge; no dexter- 
 ity; no promptness, neither proper patience; no manipulative 
 ability for their using; they require nothing but "judgment," 
 
 But the "mixing" of good plastics requires everything except 
 judgment. It requires thorough knowledge of all their attri- 
 butes during combination ; it requires, at times, exceeding 
 dexterity ; it requires, with some, a promptness which can be 
 attained but by few, and with others a patience which is not 
 possessed by all, 
 
 The act of using while the mix is setting requires peculiar 
 manipulative ability, which, while, as has been said, it can be 
 attained by a larger proportion of operators than can attain to 
 the most excellent manipulation of gold, is, nevertheless, pos- 
 sessed by few, if any^ of those whose energy has been expended 
 in the acquirement of the ability to do elegant "gold work." 
 
 Beside the spatula mixing upon the glass slab, there is the 
 " alloy mix " which is done in the " mixer " or " ager," as the 
 instrument is variously styled, and by means of which some 
 of the nicest working alloys are made from the three definite 
 alloys which have been given ; of these I may mention the 
 
TECHNICALITIES. 1^ 
 
 "mix" of submarine and contour alloys, as given, for a usual of 
 remarkable maintenance of color on articulating faces of molars ; 
 the " mix " of contour^ one part ; facing^ two parts ; as a very 
 nice front tooth for moderate sized cavities in bicuspids, cuspids. 
 and incisors ; the " mix " of submarine and contour^ equal parts, 
 where a tooth-preserving, quick-setting, contour-maker of good 
 edge-strength is indicated for a three-quarter molar crown not 
 decayed as low as the gum, etc. 
 
 There is no method, of which I am cognizant, that will so 
 thoroughly "mix" alloys as the revolving cylinder. This 
 should be revolved with only moderate speed, that the filings 
 may roll together over each other, and the " mixing " should be 
 continued for a sufficient length of time to insure completeness. 
 This for a small lot — half a dozen ounces — requires about an 
 nour. 
 
 Finally,- we have "heat mixing," by means of which the 
 powdered silex and feldspar is mixed with the molten wax and 
 gutta-percha base-plate. 
 
 Pelleting is the method by which oxy-chloride of zinc lin- 
 ings are best placed in apposition with the walls of cavities. It 
 is done by first rolling several — five or six — small pellets of 
 cotton wool, and placing the thumb-pliers and an appropriate 
 plugging instrument in readiness for use. The lining material 
 is then mixed in desired amount — preferably in small quan- 
 tity — and is taken upon the end of -the spatula and placed 
 approximately in position ; one of the cotton pellets is then 
 taken in the thumb-pliers and with it the lining is pushed more 
 accurately as desired ; the pellet is now left in the cavity, and 
 laying down the pliers the plugging instrument is used to com- 
 press perfectly the pellet and subjacent lining material. This 
 pellet is now removed immediately, before the setting oxy- 
 chloride entangles its fibres, and, if needed, another pellet is 
 pressed into position. This more perfectly dries the oxy- 
 chloride, and accurately places anj portion not previously 
 adapted. Consecutive quantities of lining are thus placed in 
 position accurately and neatly, and ia a film of such tenuity as 
 to render its shrinkage practically nothing. 
 
 Rubbing. — ^his term is used with reference to mortar- work, 
 by which is accomplished the pulverizing of ingredients, the 
 13 
 
194 PLASTICS AND PLASTIC FILLING. 
 
 compounding of powders, or the fusing of filings in mercnry 
 as they are rubbed together. 
 
 The "rubbing" of the frit prior to compounding the pow- 
 der of osy-chloride, and especially the " rubbing " of the cal- 
 cined sulphate of zinc prior to compounding the powder of that 
 pulp protector, are matters upon which depend, essentially, the 
 quality of these two compounds. 
 
 If these ingredients are not thoroughly " rubbed," neither of 
 the powders will permit of proper mixing; for an obdurate 
 grit will consume so much time for its incorporation with the 
 mass as to either deprive it of the value of a portion of mate- 
 rial or necessitate a lengthy spatulation which injures seriously 
 the setting qualities of the " mix," 
 
 The ruhhing of filings into mercury, for the making of 
 amalgam, has been specially referred to in another place. The 
 making of amalgam is best accomplished by a combination of 
 rubbing and palm-kneading ; but of these two processes the 
 possibility of the latter depends entirely upon the proper per- 
 formance of the former. It has been taught that the filings 
 should be incorporated with the mercury with a certain delib- 
 eration and yet with a degree of celerity ; but that a fluidity 
 of the first portion of the combined metals will alone permit 
 of the making of a plastic mass when all the filings are in. 
 Upon the proper plasticity of the amalgam, as the result of 
 rubbing, depends the possibility of its subsequent proper 
 kneading. 
 
 It is very easy to add a little more filings if there be too 
 great plasticity; and it is equally easy to add a little more 
 mercury if the mass is too hard, or even crumbly; but this is 
 not making an amalgam which will "test" as would a properly 
 made material. It will either set more quickly than it should, 
 and will thus be less homogeneous, or it will set more slowly, 
 and thus be less dense. Either of these conditions detracts 
 from its edge-strength, and both influence shrinkage and bulg- 
 ing, and consequently ere vicing. In short, a very good alloy 
 may thus be made to make an equally ordinary amalgam. 
 
 From time to time various materials have been suggested as 
 desirable to use in connection with the ruhhing of *the amalgam 
 mass ; some for the purpose of producing a whiter filling, or 
 
TECHNICALITIES. 195 
 
 one "wliicli would better maintain its whiteness ; some for the 
 purpose of making a quicker union of the ingredient 5 ;, some 
 for the purpose of attaining greater plasticity, etc. 
 
 These additions have been such as alcohol, chloride of zinc, 
 chloride of sodium, common chalk, spirits of ammonia, acids 
 of varied kinds and strength, from strong sulphuric to dilute 
 acetic, alum, borax, carbonate of soda, carbonate of ammo- 
 nia, etc. 
 
 It has been directed to use these in their ordinary fluid form, 
 or as crystals, or as dry powders, or as solutions ; but the in- 
 variable final process is the washing out of the adjunct with clear 
 water. 
 
 It is indisputable that some of these additions seem to produce 
 desirable results, or rather that they produced them in connec- 
 tion with the amalgams which have been generally employed ; 
 but the changes in alloy formulae, which have been given, se- 
 cure results which far more than equal any obtained from such 
 means, and the " washing " which they necessitate is, of itself^ 
 sufficient to condemn them all. 
 
 Setting is the word applied to the hardening of all plastic 
 materials used for filling teeth, or in connection with the in- 
 troduction of fillings, with the exception of such as contain 
 gutta-percha ; these are said to " harden^'' 
 
 The setting of the various plastics is quite peculiar, each ao- 
 cording to its kind; thus, "submarine" and "usual" amalgams 
 set with medium celerity. " Contour " amalgam sets with re- 
 markable rapidity ; is better set in ten minutes than ordinary 
 amalgams are in from thirty minutes to an hour. " Facing " 
 amalgam is much more deliberate, and its set is never of that 
 firmness and density which are so essential for edge -strength, 
 and particularly for contouring purposes. 
 
 The setting of zinc-sulphate, while dependent upon its thin- 
 ness or thickness of mix for promptness or deliberation, is, 
 nevertheless, always quick after it commences. It is necessary 
 that the material, if good, be mixed quite thin or milky^ in 
 order that it work at all desirably in capping or protecting 
 pulps ; for if anything approaching thick consist<;nce is at- 
 tempted, it will set not only before it can be used, but some- 
 times even before it can be well mixed- 
 
196 PLASTICS AND PLASTIC FILLING. 
 
 Thfi setting of zinc-sulphate is also peculiar in that while it 
 sets witli singular hardness, permitting a bright polish, it never 
 loses its decidedly metallic, astringent taste, but responds mark- 
 edly to a slight touch of the tongue. 
 
 It m this property which seems to give it much therapeutic 
 value. 
 
 The setting of zinc-chloride is varied both by the composition 
 and the freshness of the powder, and also by the strength and 
 condition of the fluid. For good setting^ which is quite delib- 
 erate for a zinc plastic, the powder should be well calcined and 
 reasonably fresh. When, from age, the mix does not set well, 
 it can readily be made to do so by re-calcining the powder in 
 a crucible, or, frequently, by merely placing the unstoppered 
 bottle of powder in an ordinarily hot oven for twenty or thirty 
 minutes. 
 
 The setting of oxy -phosphate is slow just in proportion as the 
 compound is poor, and is quick equally in the same ratio. In 
 some conditions of fluid, syrup, or crystal, the mass retains its 
 doughy plasticity for many minutes, — five or ten, — and is easily 
 worked and moulded during nearly all this time. This set is 
 very deceptive ; for to the uninitiated it is a most pleasing and 
 satisfactory characteristic, but with those who have witnessed 
 the failing of fillings made from such material, the slow set is 
 anything but desirable. 
 
 In other conditions of fluid, syrup, or crystal, the mass sets 
 with instantaneous rapidity, and then, usually, crumbles into a 
 coarse powder. This result, though proving the material either 
 BADLY MIXED or worthless, is better for the operator than is 
 the slow set ; for it compels him to mix anew, and thus defi- 
 nitely settle the quality of his plastic. 
 
 The setting of zinc-phosphate is quick, within reasonable 
 bounds, just in proportion as the material is good; indeed, the 
 setting of a good zinc -phosphate may be regarded as rather too 
 quick to be considered " within reasonable bounds," for it is so 
 rapid as to preclude its proper working by any except dexterous 
 manipulators. 
 
 Those who work slowly, temperamentally or habitually, can 
 overcome or modify this rapidity of setting by mixing " soft ; " 
 but the set cement will neither be so hard nor so durable as is 
 
TECHNICALITIES. 197 
 
 that whieb. is mixed with proper plasticity and manipulated 
 with proper dexterity. 
 
 Softening. — This term is applied equally to the preparing of 
 filling material for filling purposes or for the rendering of filling 
 material easy, or comparatively easy, of removal from cavities 
 of decay. 
 
 The softening of gutta-percha stopping is done in two ways, 
 which are in consonance with the requirements of the different 
 grades of the material. "Low -heat" and " medium - heat " 
 gutta-percha are softened over warm or boiling water, and 
 should never be softened in any other manner. The reason 
 for this is, that the proper heat can be secured and maintained 
 more perfectly in this way than in any other. There is also 
 'fw possibility of overheating, and thus spoiling, the gutta- 
 percha. 
 
 High-heat gutta-percha is softened by being placed on a me- 
 tallic or porcelain plate, and subjected to heat from the flame 
 of a gas-jet or spirit-lamp. Much care is needed for this soft- 
 ening, as the heat is • easily raised* to a disintegrating degree, 
 240° F., which so seriously impairs the value of the material 
 as to render it practically worthless. 
 
 The softening of a gutta-percha filling for the purpose of. 
 repairing, adding to, or removal is done by means of a heated 
 instrument, — usually a probe, either blunt or not too fine, — 
 with which the desired result is readily attained. 
 
 The softening of an amalgam filling is accomplished by drill- 
 ing the greatest possible number of small drill-holes in the 
 mass, and filling these with mercury. This is done by pouring 
 a small portion of mercury into the glass mortar, and, having 
 taken up a globule of the metal in the thumb-pliers, placing it 
 upon the face of the filling. The mercury is then worked into 
 the drill-holes by means of a small probe. 
 
 In a short time — thirty minutes or so — the mercury will have 
 so united with the amalgam as to permit of its easy drilling 
 with a good.^ sharp burr-drill. As the drilling breaks through 
 column after column of the mercurialized amalgam, the filling 
 will become more and more readily cut into, and will, not in- 
 frequently, break up into several pieces. In removing these 
 softened fillings, it is better that the cutting in two — halving of 
 
198 PLASTICS AND PLASTIC FILLING. 
 
 them — slaould be systematically aimed at, as, this having heen 
 done, it is iisually not difficult to gently force the separated 
 halves from the sides of the cavity, and thus take them away. 
 
 Shrinkage. — By common consent and habitual usage, the 
 contraction of "plastics" is called shrinkiny ; the relative 
 amount of contraction, their " degree of shrinkage ; " the in- 
 struments for determining this, " shrinkers ; " and the other 
 methods for attaining the same results, " shrinkage tests." 
 
 For ascertaining the shrinkage of amalgams, the three 
 methods which have been adopted as reliable are, the " index 
 micrometer," the " tube test," and micrometric observation, in 
 regard to each of which details have been given. 
 
 By these means great advance has been made in diminishing 
 the degree of shrinkage in all the approved amalgams, while, 
 at the same time, they have been steadily gaining in the varied 
 attributes of strength of edge, rapidity of setting, maintenance 
 of color, plasticity, and compatibility with tooth-tissue. 
 
 By micrometric observation it is shown that shrinkage of 
 good amalgam has been reduced to less than 1-lOOOth of an 
 inch in an ingot of two micrometric inches. This would give 
 as the shrinkage of a quarter of an inch filling the very small 
 degree of the tfJou of an inch. 
 
 For proving the shrinkage of gutta-percha, it is usual to em- 
 ploy the " tube test," in which an uncovered tube — small vial, 
 made of extra thick glass tubing — is carefully packed, under 
 visual scrutiny, with the preparation to be sampled, after which 
 aniline ink is poured into the vial. In a short time the shrink- 
 age of the gutta-percha is proven by the permeation of the 
 purple ink between the filling and the glass. 
 
 Ivory tubes and cups have been used for this purpose, as 
 imitating closely the actual tooth ; in these the shrinkage of 
 gutta-percha — both red and white — is demonstrated to be 
 something quite notable, as leakage takes place very freely. 
 
 The shrinkage of oxy-chloride of zinc is well demonstrated 
 by means of a small ring of glass tubing — say one-half or 
 three-quarters of an inch in diameter. This being packed as 
 for filling, and allowed to stand for a few days — three to five 
 — will show shrinkage in quantity. 
 
 The shrinkage of zinc-phosphate is tested in the same man- 
 
TECHNICALITIES. 199 
 
 ner as is tliat of zinc-chloride, and is sliown to be merely 
 nominal. 
 
 Tapping. — Tliis word, used in dental therapeutics "with refer- 
 ence to entering pulp cavities other than through cavities of 
 decay, is employed in plastic dentistry with reference to the 
 packing of amalgam. 
 
 For many years it has been directed to pack amalgam by 
 rubbing it against the walls of cavities, and upon such portion 
 of amalgam as is already introduced. It is most conclusively 
 demonstrated, by tube packing, that this is a very unsatisfactory 
 and incomplete method of inserting amalgam. It is therefore 
 directed that it be done by " tapping " the first pieces into ap- 
 position with the cavity walls, and that the consecutively in- 
 troduced pieces be made to unite, homogeneously, with those 
 previously introduced, by "tapping." 
 
 Tapping consists in delivering light blows, from the appro- 
 priate filling instruments, upon the amalgam after it has heen 
 crushed into approximate position and apposition. This " tap- 
 ping " is not to he done with mallets, either hand, automatic, or 
 electric, as a different kind of blow from any so given is far 
 preferable. The "tap " from the filling instrument — the same 
 used for crushing — is a mingled push and blow, which is soon 
 acquired, and is as promptly recognized as very efficient in pro- 
 ducing admirable results. 
 
 Testing. — This word is use'^^in reference to an immense line 
 of work which has been required by the exigencies of develop- 
 ment. , 
 
 It is such work as has been but little demanded in connec- 
 tion with the use of gold, for the " testing " of this material is 
 confined to its manipulation during insertion, while the "tests" 
 which have been applitKl to it meet with no concurrence from 
 a plastic-filler as to their value. The amount of any n^aterial 
 packed in a cavity — decided by its weight — is held by the 
 plastic-filler as of little, if any^ import as regards the tooth- 
 saving value of the filling. 
 
 The solidity of any filling, even of gold^ is regarded by the 
 plastic-filler as no criterion of the real, tooth-saving worth of 
 the work. 
 
 Even the apposition of the filling material to the walls of 
 
200 PLASTICS AND PLASTIC FILLING. 
 
 the cavity is viewed by the plastic-filler from his peculiar stand- 
 point ; for he notes the constant failure of the gold fillings with 
 their elegant microscopic adaptation, and the wonderful preser- 
 vation aftbrded by gutta-percha with its known deficiency in 
 that respect ; thus it is that the circumscribed line of work in 
 the " test " packing of gold, surrounded as it is with the high- 
 sounding epithets of " artistic," " elaborate," " ideal," etc., is 
 viewed by the plastic-worker with mingled wonder and amuse- 
 ment, and is thought to have but little " weight," less " solid- 
 ity," and no appreciable " apposition " to the great question of 
 tooth-salvation. 
 
 The " test work " of plastics is the natural result of a multi- 
 plicity of materials and of the desired modifications in connec- 
 tion with numerous compounds. Not alone have the attributes 
 of silver, tin, gold, copper, zinc, mercury, gutta-percha, oxide 
 of zinc, sulphate of zinc, chloride of zinc, nitrate of zinc, 
 borate of soda, the acids of phosphorus, alcohol, the gums of 
 mastic, sandarac, copal, caoutchouc, and acacia, oxide of tin, 
 wax, sulphite of lime, feldspar, and silex to be considered, but 
 the endless variety of composition in which these ingredients 
 may be advantageously employed ; and when to these are 
 added the " questionables," of doubtful value, but which have 
 claims that entitle them to attention, such as antimony, bis- 
 muth, cadmium, palladium, alumina, gypsum, chalk, alum, 
 kaolin, and quick-lime, is it strange that the word " testing " 
 has a meaning for the worker in plastics beside which the repe- 
 titions that have formed the " discussions " of dental societies 
 for the past twenty years seem like time-wasting trifling ? 
 
 On the one hand, we have the rehash of methods and manip- 
 ulations which have resulted in making it questionable whether 
 the title of "permanent denture" is most appropriately applied 
 to natural or artificial teeth ! while on the other, we have that 
 work which by " testing " has resulted in materials, methods, 
 and manipulations whicll fairly bid defiance to the ravages of 
 caries, and make of the frailest and softest teeth wonderfully 
 ^^ permanent dentures.^'' 
 
 In a paper which was read before the American Dental As- 
 sociation, Niagara Falls, August, 1878, — not •puhlislied in the 
 Transactions^ — reference was made to the statement, from one 
 
TECHNICALITIES. 201 
 
 of those to whom students of dentistry look for instruction, 
 that plastic work was "-guess worhy To this 1 replied that 
 "so far from being '■guess work^^ we have a range of 'tests' 
 which tell us very well what we may expect of any material 
 under given conditions. These are such as strength test, edge" 
 test, setting test, shrinkage test, expansion test, color test, heat 
 tests (wet and dry), leakage test, frotting test (for probable 
 wear), acid test, alkali test, conduction test (electrical and ther- 
 mal), and finally the oral test, which decides the compatibility 
 of materials with tooth-bone and their behavior in the oral 
 jiuids and under oral influences. 
 
 '■''By means of these tests we are enabled to make a choice of 
 material to meet the varied indications that constantly present in 
 practice^ which^ to our apprehension^ approaches to SOMETHING 
 LIKE SCIENCE. 
 
 " It is by these means that we frequently combine two, three, 
 four, or more different materials in the filling of one cavity, 
 each of which best subserves its purpose in its appropriate po- 
 sition, and insures an operation which for comfort, beauty, and 
 permanency can in no other way be equalled." 
 
 All this is so entirely at variance with that stereotyped prac- 
 tice which it is the duty of the publishing committee to place, 
 year after year^ before the profession, that it seems " reasonable 
 and consistent " it should be deemed imperative to suppress it. 
 
 This alone would doubtless have been sufficient to decide 
 the action of any dental publication committee, but when to it 
 was added the assertion that Plastic Dentistry "is even now a 
 very well worked-up specialty of our profession ; one that is so 
 little knoivn as scarcely to be mentioned except with contempt or 
 disapprobation from the lecture stand^ AND YET one which can 
 now take any denture so forlorn as to be HOPELESSLY abandoned 
 by the best gold operator in the world and make of it a 
 COMFORTABLE, SATISFACTORY, and BEAUTIFUL SUCCESS," then 
 suppression of such a damaging assertion, particularly if it was 
 in the least degree probable that it could be sustained, became 
 a duty which, in its magnitude, was simply overwhelming. 
 
 What an extraordinary thing is the sense of duty.* 
 
 I have felt it my duty to place these statements before my 
 professional brethren because they have all been made as the 
 
 * Eefer to letter of " Publication Committee" of American Dental Association, p. 61. 
 
202 PLASTICS AND PLASTIC FILLING. 
 
 results of long and tliorough '■'■testing ;'''' "because I am conversant 
 with tlie continued, persistent work which has been required to 
 do this ; because I know of the earnest interest with which the 
 work has been done ; because I know of the thousands of 
 patients who have realized the benefits of the work ; because I 
 know of what I speak — that it is capable of demonstration 
 that it is true ; because I feel that mj profession needs it; be- 
 cause I feel that suffering humanity needs it ; because I feel that 
 the cause of progress demands it. 
 
 Thus it is that in my "decision " I arti "actuated by personal 
 prejudice." I do consider the statements of " sufficient value " to 
 warrant their presentation ; I am " influenced by " most decided 
 " opposition to the doctrines advanced " in the usual dental con- 
 tributions ; and I also am " governed solely by a sense of dutyT 
 
 Trimming refers to the cutting away or removing of siirplus 
 filling material. In plastic filling, it is almost universally the 
 case that a superabundance of material is introduced. This is 
 due to the fact that no more time, if as much, is required to 
 more than fill any cavity than would be needed for the accu- 
 rate filling of the same. It is also found to be advantageous 
 that an ample amount of filling be given for final shaping. It 
 is less difficult to remove surplus than it is to add on. The 
 materials are comparatively inexpensive, and thus " waste " 
 does not involve much "loss." The removal of, surplus does 
 not necessitate inflictive or disagreeable instrumentation, such 
 as hand-filing, chiselling, stoning, etc., as is the case with gold. 
 
 In trimming amalgam fillings, all grades of tool-edge are not 
 only admissible but desirable, from the sharp edge of the 
 " trimmer " to the absolutely round edge of the curved bur- 
 nisher. This latter is particularly useful and non-inflictive for 
 trimming the fillings and making smooth adaptation of filling 
 with cavity edge below the gum, especially on buccal faces; 
 while the thin-edged, paper -like separators are admirably cal- 
 culated for trimming between teeth. 
 
 For trimming fillings of gnitta-percha, I use exclusively 
 heated instruments, several of which being heated at once upon 
 the " tool-heater," it is easy to adapt varied shapes to varied 
 requirements. 
 
 For trimining zinc-phosphate fillings, sharp-cutting instru- 
 
TECHNICALITIES. 203 
 
 ments are required, sucli as knife-edged trimmers, bnrrs, and 
 files. These should be kept perfectly dry or thoroughlj wet, 
 as by these means the filings or cuttings are either dry powder, 
 which can be blown away, or make, by free dilution, a milky 
 fluid which does not seriously clog either burr or file. 
 
 Trunnioning. — It is by this operation that amalgam buffers 
 of all sizes are retained firmly in position, when they do double 
 duty in that they prevent wear from attrition upon gutta- 
 percha guards, and disintegration, by fluids of the mouth, of 
 oxy-chloride linings. Suppose a cavity in a molar or bicuspid, 
 mesial or distal, reaching up to or under the gaim, nearly into 
 the pulp, extending partially over the articulating face of the 
 tooth, and having very frail, thin walls both buccally and 
 lingually. This condition is frequently found in bicuspids of 
 soft structure which have been filled repeatedly with gold. In 
 such the cervical edge is first guarded by a layer of gutta- 
 percha, which is neatly extended far enough into the cavity to 
 prevent pulp irritation frora conduction after filling, and from 
 zinc-chloride irritation during lining. The cavity is now lined 
 buccally and lingually with oxy-chloride of zinc, which is al- 
 lowed to set thoroughly, covering it temporarily with "tempo- 
 rary stopping " for an hour or two,- or a day or so if more con- 
 venient. 
 
 When the zinc lining is perfectly set, an indentation or pit 
 is drilled into each side of it, buccal and lingual, as large as is 
 consistent with strength ; a contour amalgam filling is now 
 made, Avhich by entering the drill-pits becomes held by trun- 
 nions^ and thus solidly maintains its position. 
 
 Wafering. — Upon the intelligent utilizing of this process 
 depends largely the comfort, satisfaction, and success of amal- 
 gam work. It consists of making wafers of small portions of 
 amalgam, and using them for the purpose of increasing the con- 
 sistence of amalgam which has been introduced soft for some 
 specific object, as prevention of pulp irritation, prevention of 
 too severe impinging upon exquisitely sensitive or heavily de- 
 . calcified dentine, or, to facilitate its insertion into some exceed- 
 ingly inaccessible location; or to increase normal consistence of 
 already introduced amalgam for the purpose of hastening set- 
 ting, and thus 'permitting prompt continuance of work, as in 
 
204 PLASTICS AND PLASTIC FILLING. 
 
 building; or for tlie hardening of the face of a filling, that the 
 work of finishing may be facilitated, while at the same time 
 an increase of edge-strength and a whiter face may be insured. 
 
 The wafer is made by taking a small portion of the amalgam 
 and folding it in a piece of "chamois-skin; " the chamois is now 
 twisted so as to secure the amalgam and prevent such escape of 
 mercury from squeezing, as may permit of its again being 
 taken up from contiguity by the wafer. 
 
 The squeezing of the amalgam should be done with large, 
 strong pliers — as illustrated — made expressly for this purpose ; 
 these are about seven inches in length, with flat, round-edged 
 jaws — so as not to cut the chamois-skin — and are properly 
 adapted to thorough squeezing with the expenditure of com- 
 paratively little force. 
 
 This is an important consideration, for, with ordinary sized 
 pliers, either the squeezing would be insufficient, or the force 
 required would be inflictive to the hand. The difference in the 
 physical characteristics of wafers made by using the ordinary 
 pliers and those made by the appropriate pliers can only be 
 realized by comparison of the two results, and the success of 
 wafering is widely different when done by thoroughly -squeezed 
 instead of half -squeezed " wafers." 
 
 Washing. — I have merely introduced this term that I may 
 once more enter a protest against the process to which it refers. 
 Every experiment points to the inutility of " washing " amal- 
 gam ; every experiment indicates that it is worse than useless ; 
 that it is detrimental. It is conceded that fillings made with, 
 submarine amalgam would, theoretically, be better made if done 
 dry ; while the fact that good results follow wet work is only 
 urged in the humane effort to accomplish respectable tooth- 
 saving without the necessity for dire infliction. Therefore, 
 I should condemn any process, in connection with the making 
 of amalgam, which entailed, as a part of its performance, the 
 washing of the material. 
 
 Weighing. — In plastic filling this word refers only to the 
 manner of determining the relative quantities of mercury and 
 filings required for the making of any definite amalgam ; or 
 for the modifying of the known best make of any given amal- 
 gam that exigencies may be accurately met. 
 
TECHNICALITIES. 20(j 
 
 I think it sufficient to prove the importance which I attach 
 to the weighing of the ingredients for making amalgam, when 
 I state that, with the daily experience which I have had foi 
 nearly twenty-five years, I never make amalgam without weigh 
 ing the proportions. 
 
 Recognizing completely the necessity for accurate compound- 
 ing in the obtaining of definite results, I know that / cannot 
 even closely approximate the desired amounts of mercury and 
 filings, and I further know that if I could it would not be suffi- 
 ciently accurate for my purpose. 
 
 Upon very many occasions, I have requested, from those 
 who claimed ability to "judge " with " reasonable accuracy " in 
 this apportionment, demonstrations of their skill, and I think 
 the sequence has been, almost universally, a determination upon 
 the part of the experimenters to weigh their proportions in 
 future. 
 
 The fact is, no one can secure anything more than a very 
 rude approach to the required amounts of mercury and filings 
 for the making of amalgam, if this is done by the "judgment " 
 method ; whereas, by the weighing method, one can soon be- 
 come so expert as to prognose the consistence or plasticity 
 which will pertain to nearly every " make " of amalgam mass 
 hefore it is rubbed. 
 
 This is what is required ; for thus it is that the proper plas- 
 ticity for meeting special indications is given any appropriate 
 selection of amalgam ; thus, a submarine mass, which is to be 
 used in an accessible cavity upon the buccal face of a lower 
 first molar, would naturally be made of firm, workable con- 
 sistence ; while the same alloy would, as appropriately, be made 
 into an amalgam of soft plasticity, if the cavity to be filled were 
 exceedingly inaccessible, and was possessed of frail walls, spot- 
 tings of excessively sensitive dentine, or other like complica- 
 tions. 
 
 By weighing, all these important considerations are promptly, 
 neatly, and accurately met; and I think that years of practice 
 will only serve to demonstrate to others that which has been 
 demonstrated to me, viz., by no other method than weighing, 
 can satisfactory making of amalgam be accoraplished. 
 
 I will repeat, that the iveighing is not to be done with weights, 
 
206 PLASTICS AND PLASTIC FILLING-. 
 
 but by weiglit ; and I would say, that altbougb tbe making of 
 amalgam from reliable alloys is always done with an a'p'proxi- 
 mately horizontal scale beam, yet, to tlie expert, the slight de- 
 viations from this are the means by which he uniformly accom- 
 plishes any desired modification. 
 
 Whitening. — This term is applied alike to teeth and to 
 fillings. In plastic dentistry, the ^^ bleachinc/''^ of teeth is 
 ignored as a detrimental and non- compensating process, and 
 consequently the word has become obsolete. 
 
 In the article on oxy-chloride of zinc, its use as a whitener 
 of teeth has been explained, and reference has been made to 
 the permanence which attaches to this restoration of color. 
 
 In the article on " insertion of amalgam," the peculiar method 
 of white finishing has been described ; but as this was then only 
 one point among many, and as considerations of beauty have 
 obtained notable prominence in " plastic- work " ever since 
 reaching conclusions upon the practical problem of tooth-salva- 
 tion^ I regard it as proper to direct attention again to the fin- 
 ishing of amalgam fillings. 
 
 After the required ten or fifteen minutes of setting, an amal- 
 gam filling may receive, if needed, its accurate contouring by 
 trimming, and should then have its second finishing from the 
 piece of pine stick as described in the article referred to. 
 
 This finishing results in a white face, which, though yet of 
 comparatively coarse grain, is nevertheless much finer in ap- 
 pearance than was the • grain given by the first smoothing. 
 Again, ten minutes or so should be given for further setting, 
 when the filling may be finally finished. The final finish is 
 given by the soft pine stick, but it is sometimes found necessary 
 to add to this a \\i\\e finely levigated pumice. This is made by 
 putting in a basin part filled with water a small quantity of such 
 pulverized pumice as is usually sold. It is then thoroughly 
 stirred up, and allowed to settle perfectly. The clear water, 
 with the floating impurities, is then poured off. The basin is 
 again partially filled with water, and the pumice again thor- 
 oughly stirred up. This is then allowed to settle for s^few 
 seconds — four or five — when the milky fluid is poured off, and 
 the fine pumice contained in it is permitted to settle until the 
 
COK"CLUSION. 207 
 
 water is again perfectly clear. The clear water is poured ojff", 
 and the remaining fine sediment is dried for use. 
 
 When the final finish is given, it will be noted that the most 
 decided whitening is accomplished by smoothing the face of the 
 filling in a downward or upward direction, — as it is in an upper 
 or lower tooth, — and not across the filling disto-mesially . 
 
 This method of finishing leaves a striated surface, which, 
 though microscopic in the fineness of its markings, yet pre- 
 sents a succession of faces upon which the light impinges di- 
 rectly, and by which a reflected whiteness is given to the filling. 
 
 CONCLUSION. 
 
 With this I am permitted to see the end of a work which 
 was commenced a quarter of a century ago. Its possibilities 
 were then discussed, its probabilities foretold, but the view of 
 its realization — then, to a few, an ideal of the far-off future — 
 has been granted to me alone. 
 
 Although it is with grateful satisfaction that I now contem- 
 plate the gradual development of that which has been the 
 medium for so much alleviation to suffering, so much bestowal 
 of long-enduring comfort, and such incontestably beneficial re- 
 sults, it is yet with mingling of regret and pleasure that I cast 
 it forth to do battle in the struggle for professional place and 
 precedence. 
 
 I shall regret to see it frowned upon ; I shall regret to see it 
 misrepresented, and yet I can but know that it must meet with 
 the common reception of those numerous predecessors which 
 have waged war against " accepted doctrines ; " but it is to me 
 a pleasure indeed that I am, even yet, afforded ample oppor- 
 tunity for the practical demonstration of the truths of its teach- 
 ings, and that strength is yet given me to raise my voice in its 
 defence. 
 
 I ask for it a serious, thoughtful consideration, and sincerely 
 hope that much good may come of it. 
 
APPENDIX. 
 
 Section 1. Eefer to page 65. — A valuable suggestion Las 
 "been made by Dr. J.F. Siddall, which consists of " Heat Ageing " 
 freshly-cut alloys. This is done by applying a moderate degree 
 of heat to the filings for the space of ten or fifteen minutes.* 
 Experiments have proved that the best method for doing this 
 is that of placing the filings in any convenient receptacle, and 
 subjecting them to the heat of boiling water. By this device 
 one is enabled to use freshly-cut filings with much satisfaction ; 
 but I have found that they will yet gradually improve by " time 
 ageiug," even after having been subjected to this process. An 
 excessive degree of heat will render fresh filings of " excel- 
 lent " quality almost completely devoid of " setting " power,. and 
 it is therefore important that the security of the water-bath 
 should be utilized in prevention of this possible result. 
 
 Section 2. Eefer to page 67. — A very desirable form of 
 mercury holder has been invented by Dr. J. H. Kidder, and has 
 been thought well worthy of illustration (see opposite page 90), 
 as it has proved markedly economical. 
 
 By a gentle turning of the upper section of the holder, a 
 quantity of mercury exactly proportioned to any given require- 
 ment is forced through a minute orifice into the inverted cone- 
 shaped receptacle, and from this is emptied into the scale-plate. 
 
 This ensures the use of only an equally just amount of filings 
 for each " make " of amalgam, and the saving which is thus ac- 
 complished is really a matter of much moment. I have found 
 the simplest form of this instrument the heat^ and that which 
 has the orifice at the bottom of the cone much preferable to that 
 which has the orifice upon one side. 
 
 Section 3. Eefer to page 90. — In writing of " ground glass " 
 mortars, I have reason to fear that the usual idea which is at- 
 tached to the term " ground glass " has overshadowed the state- 
 ment, "but if the glazed surface is delicately taken off' the in- 
 
 * For small quantities of alloy, from five to eight minutes' heating is suflBcient. 
 
 208 
 
APPENDIX. 209 
 
 side of tlie glass mortar, it will prove much, superior to porcelain." 
 I therefore desire to impress the fact that mortars should not be 
 " ground," in the ordinary acceptation of that term as applied 
 to glass, but that onlj the smooth and polished glaze should be 
 " delicately " removed from the mortar by means of flour of 
 emery and a piece of cloth or pestle-like piece of wood. 
 
 The bulbous portion of the pestle may be treated in the 
 same manner. 
 
 Section 4. Eefer to page 102. — From many remarks in re- 
 lation to discoloration of submarine amalgam, I am led to in- 
 fer that the phrase " if exigencies demand it " has not been 
 sufficiently expressive, I have reason to place great reliance 
 upon this excellent alloy ; so much so, that were I to have to 
 make choice of but one filling material with which to practise 
 dentistry, I should unhesitatingly choose this. So far from being 
 liable to discolor, it is a notable color-keeper under ordinary 
 conditions. By reference to pages 50 and 51, it will be seen that 
 whiteness is one of the attributes ascribed to accurate additions 
 of copper, while the peculiar property of copper is in place, 
 page 48, referred to when so acted upon as to form the sulphide. 
 
 So long as "decay "does not progress, submarine amalgam 
 maintains an acceptable whiteness ; but if recurrence of decay 
 occurs, there is, as a necessary concomitant, the evolution of sul- 
 phuretted hydrogen, and " exigencies demand " a discoloration 
 alike of amalgam and dentine. Discoloration then becomes 
 equally acceptable with maintenance of color under other con- 
 ditions, as discoloration is indicative of the best known effort at 
 arrestation of decay. 
 
 Section 5. Eefer to page 168. — While it is productive of a 
 better zinc-phosphate cement if the mass is taken from the 
 spatula and gently kneaded, it is nevertheless advisable that it 
 be occasionally used when only spatula mixed. This is espe- 
 cially the case when " facing " is to be done and when " linings " 
 are to be made. In " facing," the mass should be made ^oft and 
 placed in position from the spatula, — No. 12 of the set of in- 
 struments, page 93, — and then worked into place and pressed 
 into contour by instruments 6, 7, 8, oiled. In " lining," cements 
 
 made from oxide of zinc and the fluid of zinc-phosphate, or a 
 14 
 
210 APPENDIX. 
 
 mixture of oxide of zinc and nitrate of zinc with the zinc-phos- 
 phate fluid, will be found to work very nicely, producing good 
 shades, retaining their plasticity desirably, and hardening suf- 
 ficiently for strength and durability with reasonable celerity. 
 
 Section 6. Eefer to pages 171 and 172. — During the past 
 year, I have been experimenting with various preparations for 
 the more prompt and effectual exclusion of moisture from 
 zinc-phosphate fillings, as I have been decidedly impressed with 
 the importance of this aid to their durabilit}^. Up to the pres- 
 ent time I have tried nothing which has worked better than an 
 "adhesive wax" composed of white wax 1 part, resin 5 parts;* 
 melt over sand-bath and stir thoroughly together. Work it and 
 make it into sticks, using powdered soapstone freely to prevent 
 adhesion to the fingers. This wax is used by heating instru- 
 ment No. 7, and taking a small portion and placing it, molten, 
 upon the filling. By reheating the instrument, the surface of 
 the filling can usually be nicely covered with a thin coating 
 of wax, which hardens almost immediately and adheres with 
 much tenacity. Upon articulating fillings, it is better to spread 
 the wax by heating, quite hot. No. 2 ball burnisher, after having 
 placed the wax in position by No. 7. For cleaning the instru- 
 ments after using wax, they should be heated, and wiped off with 
 paper. This is an easy and satisfactory method of accomplish- 
 ing a somewhat troublesome task. 
 
 Section 7. Eefer to page 174. — As an improved recipe for 
 the making of "Temporary Stopping," I would give the fol- 
 lowing : 
 
 R. White wax 1 dwt. (full) 
 
 Eed Gutta-percha base plate .... 4 dwt. 
 Precipitated Chalk 4 dwt. 
 
 Melt and mix as directed at ' page 174. When mixed, take 
 a convenient sized portion and roll it into a ball between the 
 palms of the hands; then placing the ball upon any smooth 
 surface, roll it gently into a stick by the fingers of an open hand. 
 Smoothly round the stick by rolling it with a piece of flat wood 
 or plate of glass. 
 
 Temporary stopping, although not absolutely a " tight " filling 
 material, is nevertheless that one which makes decidedlv the 
 
 * Dark resin 5 parts ; refined resin 10 to 12 parts. 
 
APPENDIX. 211 
 
 best " testings for leakage" of any of tlie gutta-percha mixtures. 
 It is therefore very valuable for filling pulp cavities over canal 
 dressings or inspissated medicaments, and for guarding or cov- 
 ering arsenical applications. 
 
 The varied utility of this material is such as to have already 
 ranked it as one of the "indispensables" to the practice of den- 
 tistry. 
 
 Section" 8. Eefer to page 104. — By reference to page 57 it 
 will be seen that cadmium experiments were suggested as ad- 
 visable if conducted with great care. In the direction of 
 "Facing" alloy these have been made with the promise of an 
 increasedly satisfactory color keeper. The basal formula, at 
 present, is tin, 60 ; silver, 30 odd ; cadmium, 5 to 10. 
 
 Alloys of this nature should never be used in contact with 
 tooth tissue. 
 
 SECTloisr 9. Eefer to page 63. — As it has been noted that by 
 the addition of the cold granulated silver the melted tin is in 
 some degree cooled, it has been suggested by Mr. Eckfeldt that 
 the silver be first heated to a low red heat ; the tin is then 
 placed in the crucible, and, melting almost immediately, a 
 prompt fusion and combination of the silver ensues, after which 
 copper, gold, etc., may be added. 
 
 N. B. — In text references to dates, I desire it shall be remembered that these 
 are given as dating from 1881. 
 
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 DATE DUE 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 DEMCO 38-296 | 
 
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