Columbia Winibtx^itp inti)eCitj>ofi^eto^orfe College of ^f)pgidans! anD ^urgeonsi Reference Hihxatp Presented oy %^DR. WILLIAM J. OILS iM" fo enrich the library resources *" availaSle to holders of the ^B GIES FELLOWSHIP f^/^ tf2 Biolosic&l Chemistry Digitized by the Internet Archive in 2010 with funding from Open Knowledge Commons http://www.archive.org/details/principlestechniOOhove Principles and Technique OF Crowns and Bridges By J. F. HOVESTADT. D.M.D. Instructor in Crown and Bridge Work, Harvard Dental School, Harvard University Former Vice-President of the Massachusetts Dental Hygiene Council Member of: Harvard Odontological Society Massachusetts Dental Society First District Dental Society, State of New^ York National Dental Association BOSTON, MASSACHUSETTS RITTER & FLEBBE 120 BOYLSTON STREET (The right of reproduction of the original illustrations is strictly reserved.) Copyrighted at the Registry of Copyrights, Wasliington, D. C, igiS All rishts reserved. CONTENTS I. INTRODUCTION ""l II. EXAMINATION AND STUDY OF GROWN AND BRIDGE GASES . . 11 III. GLASSIFIGATION OF GROWN AND BRIDGE GASES 13 A. AS TO HEALTH AND PATHOLOGI- CAL CONDITIONS OF THE TEETH AND MOUTH 13 1. Septic roots 13 2. Acid mouth and erosion .... 15 3. Pyorrhoeatic condition 15 4. Absorption of tissue 18 B. AS TO OCCLUSION 20 1. Normal occlusion 20 2. Sufficient occlusion 20 3. Mal-occlusion 21 a. Lack of contact points ... 22 b. Teeth tipped forward ... 22 c. Teeth elongated 24 d. Temporary teeth retained • 26 e. Closed bite 27 f. Maxillary and mandibular] pro- tusion 29 g. Wandering teeth ^^ h. Irregularly arranged teeth . • 33 CONTENTS IV. PRELIMINARY TREATMENT OF THE p,,e MOUTH AND TEETH 37 1. Prophylactic treatment 37 2. Exodontia 37 3. Pyorrhoea treatment 37 4. Devitalization of healthy teeth . 37 5. Treatment of teeth with pathological pulps 38 a. Treatment from root canals . 38 b. Treatment from alveolar side, surgically 42 6. Building up of decayed and broken- down teeth 43 V. ORAL ANAESTHESIA 44 A. INSTRUMENTARIUM 44 B. DRUGS 47 G. PREPARING OF SOLUTION ... 47 1. For normal cases 48 2. For deep anaemia 48 3. For abnormal cases 48 D. PREPARING OF PLAGE FOR IN- SERTION OF THE NEEDLE . 49 E. INFILTRATION METHOD .... 49 1. Injection in buccal and labial side of maxillary teeth .... 51 2. Injection on labial side of lower in- cisors 52 3. Injection on palatal and lingual sides • 52 F. CONDUGTIVE METHOD .... 54 1. Pterygo-mandibular injection ... 54 2. Buccinator injection 57 3. Zygomatic injection ...... 57 4. Infra-orbital injection 58 5. Incisive injection 58 6. Post palatine injection 59 G. AFTER-EFFEGTS 59 PULP REMOVAL: PRESSURE ANAES- THESIA 59 TREATMENT FOR HYPERSENSITIVE DENTIN 60 CONTENTS Page VI. GENERAL TECHNICAL MANIPU- LATION 61 1. Selecting shade 61 2. Taking bite 61 3. Taking impression 61 4. Mounting a Grown and Bridge case on articulator 63 Selecting of teeth 64 Grinding of teeth 64 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. Backing of teeth 65 Reinforcing or backings .... 66 To prevent cracking of facing ... 67 Soldering bridge in sections ... 69 Gasting . 70 Polishing 72 Gold plating 73 Fitting bridges in mouth and wearing them 74 Cementing 75 Final adjustment of occlusion 76 Instruction to patients ..... 76 Care of bridges 77 VII. SINGLE CROWNS ALL PORCELAIN CROWNS Crown I 1. Jacket crown 2. Detached post crown Crown II Detached carved crown Grown III Detached stock crown . 78 78 78 81 81 82 PORCELAIN CROWN WITH METAL BASE 88 Crown IV 1. Porcelain baked crown with platinum base 88 Grown V 2. Porcelain crown with cast base • . 89 Direct Method 89 Indirect Method 90 CONTENTS Crown VI Grown VII Grown VIII Grown Via Vila Villa BANDED GROWNS 92 I. Base for Banded Growns . . 93 Direct Method 93 1. Soldered caps 93 2. Burnished caps 95 Indirect Method . . ... .96 3. Swaged caps 96 II. Supplies for Banded Growns . 97 a. With facings 97 Grown VIb Vllb Vlllb Grown Vic VIIc VIIIc b. With detached post crowns c. With Goslee teeth 98 100 Grown VId Vlld Vllld d. With Steele teeth 101 Grown IX 1. Grown XI 3. XIa Xlb Grown XII 4. Grown XIII 5. Grown XIV 6. ALL-METAL GROWNS . . . Open-faced crowns — glove fit Two-piece all-metal crowns a. With swaged cusps . b. With cast cusps Seamless pressed crowns • Seamless swaged crowns . Growns with porcelain facing 102 102 105 106 107 108 113 118 CONTENTS Page VIII. FIXED BRIDGES 119 A. ABUTMENTS FOR FIXED BRIDGE- WORK 119 A. Inlay Abutments 119 Abutment I 1. Inlays with posts or M. O. D. inlays . 119 B. Banded Grown Abutments . . 122 I. BASE FOR BANDED ABUTMENTS ... 122 Abutment II 1. Soldered caps 122 Abutment III 2. Burnished caps 122 Abutment IV 3. Swaged caps 122 II. SUPPLIES FOR BANDED ABUTMENTS . . 122 Abutment Ila-IIIa-lVa a. With facing 122 Abutment Ilb-IIIb-IVb b. With detached post crown. 122 Abutment IIc-IIIc-IVc c. With Goslee tooth .... 122 Abutment Ild-IIId-IVd d. With Steele tooth 122 C. All-Metal Abutments ... 123 Abutment V 1. Half crown with post 123 Abutment VI 2. Staple 124 Abutment VII 3. Open-faced, glove fit 126 Abutment VIII 4. Open-faced, other methods . 126 Abutment IX 5. Two-piece all-metal crown Swaged cusps 126 Cast cusps 126 Abutment X 6. Seamless pressed crown .... 126 Abutment XI 7. Seamless swaged crown .... 126 Abutment XII 8, Grown with porcelain facing . . . 126 B. SUPPLIES FOR BRIDGEWORK . . 126 Supply I 1. Gast supplies 127 Supply II 2. Facings with double backings . . 128 Supply III 3. Facing with backings and swaged cusps 128 Supply IV 4. Detached post crowns 130 Supply V 5. Steele facings 130 Supply VI 6. Steele posterior 131 Supply VII 7. Goslee teeth 134 Supply VIII 8. Evslin interchangeable teeth 136 CONTENTS Page C. ASSEMBLING BRIDGES 137 Bridge I 1. Sanitary bridges 137 Bridge II a With gold chewing surface. ... 137 b With porcelain chewing surface . 138 Bridge III 2. Self-cleansing bridges 138 Bridge IV 3. Saddle bridges 140 With continuous saddles .... 140 Bridge V With porcelain saddles 142 With individual saddles 143 Bridge VI 4. Extension bridges 144 Bridge VII 5. Interlocking two-piece bridges 144 Dove-tail attachment 144 IX. REMOVABLE BRIDGES 145 A. Gilmore attachments 145 General description of technique 145 Preparing caps and posts 145 Fitting platinized gold wire 147 Bridge I 1. Full bridges 156 Bridge II 2. Short bridges 158 Bridge III 3. Partial bridges with vault bar . . . 158 Bridge IV 4. Partial bridges with lingual bar . . 160 Bridge V 5. Extension bridges 160 Bridge VI B. Removable bridges with Roach attach- ment 168 Bridge VII C. Removable bridges with Morgan attach- ment 169 X. REPAIR OF CROWNS AND BRIDGES 174 1. For temporal use 174 2. For permanent use 177 Ash repair outfit 178 Steele repair outfit 179 Bryant bridge repair tools .... 180 Another method 180 Mineral stains 182 Special instruments 182 XL PRACTICAL CASES 185 I. INTRODUCTION IT is the author's aim to give in this book a practical, systematic and condensed description of the technique of Crown and Bridge work. The book is specially written for the student, and the prac- titioner, who has had little experience in this branch of our profession, to help him restore the vital function and character- istic beauty of the masticating apparatus. Realizing the great importance which so often is overlooked, to make a careful study of a mouth, so as to be able to follow a definite plan of restoration, the author has tried to make the less experienced reader acquainted with mal-occlusion resulting from the loss of teeth, which have not been replaced, and mal- occlusion in the adult resulting from other reasons. Also the condition of the teeth, to serve as abutments, should receive close attention. As it would be unwise to build a beautiful new house on an unsafe foundation, so it would be condem- nable to use unhealthy teeth or roots, as abutments for a bridge. The author therefore will also bring close attention to such conditions, and point out the importance of making careful ex- aminations of such teeth, which should be extracted if they do not yield to treatment. BridgeAvork as a rale recjuires the most extensive reduction of the shape of the teeth and if, after careful study, it is found necessary to devitalize a tooth, one can accomplish this in no other way with such ease, with so little pain, and so much saving of time, as with the aid of "Local Anaesthesia," the importance of which has not yet been sufficiently recognized, and therefore a very condensed chapter on "Local Anaesthe- sia," an extract from Dr. K. H. Thoma's book "Oral Anaes- thesia," has been added by special arrangement with my es- teemed friend and co-worker. Crown and fixed bridge work will then receive our atten- tion. The technique is given in step form, with illustrations to make it as simple as possible to follow, one after the other, 10 INTRODUCTION the steps of construction. The author considers well-con- structed fixed bridgework the best known replacement, as it is closest to AA^hat nature intended us to have. However, the cases must be properly selected. Eemovable bridges help us in many cases to overcome conditions, Avhich are unfavorable, and unpractical for fixed bridges, and these render it possible in many cases to give the patient a satisfactory and comfort- able appliance, especially when it would be almost impossible to get a good result with a plate. The author's experience is based upon twenty-seven years of practical work, conducting his own laboratory, as AA^ell as directing the work for other practitioners, consisting chiefly of metal and porcelain work. During this long period of private practice and seven years of teaching in the Crown and Bridge Department of Harvard Dental School, the different methods have been given the most careful tests. The principal aim is to give the inexperienced, |a reliable guide, and it is the author's sincere hope and wish that the reader may benefit humanity, through knpwledge received from this book, and receive in return the appreciation of his patients. II. EXAMINATION AND STUDY OF CROWN AND BRIDGE CASES It is of greatest value that the entire mouth should be studied when a case presents itself for Crown and Bridge work. Too many men let themselves be influenced by patients desir- FiG. 1. These two cases show the result of work done without the help of Radiographs. ing to improve their appearance, and therefore asking for replacement of some particular teeth only, disregarding con- ditions in the masticating region, which are of much greater importance. It is the dentist's duty to point out the double 12 CROWDS AND BRIDGES advantage of restoring the normal occlusion. Not only should hopeless teeth be extracted, sufficient roots treated, cavities filled, but the posterior teeth should be replaced first of all, to give the patient the possibility to masticate and in this fashion improve his general health. Beside the improvement of health and efficiency, we have another reason which is very closely associated with the operator's success. If teeth are only restored by bridges in parts of the mouth, while spaces remain in others, we get abnormal pressure, and abnormal force ap- plied upon the artificial appliances, shortening the time of service of their abutments. A dentist is therefore more than justified to refuse treatment, if the patient does not commit himself to the operator's advice. As in orthodontia so in Crown and Bridge Models work, it is most satisfactory to study a mouth with the aid of plaster models. It is not only much easier to study the conditions on models, but these will be a help to consult and advise the patient. Finally they will be a record of the primary condition of the mouth. The teeth to be used for abutments, should Radiographs be carefully studied. The condition of the pulp, direction of the roots, number of roots and canals, and in devitalized or septic teeth the condition of the apex should be ascertained. In pyorrhoeatic cases, we should know how much of the process has been absorbed. All this is easily done by radiographs, which give us a good idea beforehand how strong the fundamentals are upon which we base our work. III. CLASSIFICATION OF CROWN AND BRIDGE CASES We can classify a nioiitli in two ways: (a) Pathological conditions of the teeth and mouth. (h) In regard to occlusion. A. PATHOLOGICAL CONDITIONS OF THE TEETH AND MOUTH Patients needing bridgework have usually brought about the loss of teeth by negligence of their mouth, and we there- fore frequently find their teeth in very bad condition. Often we find diseased teeth, and we have 1. Septic to decide just what teeth should be saved, Roots and what teeth should be extracted. To de- cide this question, we must consider that a tooth has a relative value. If there are plenty of good abut- ments, we will condemn a tooth, with a chronic alveolar ab- scess, which has given trouble from time to time, but in case of scarcity, it would be important to treat this tooth, even if it involves a long and tedious process. For example, it might be of practical value to save even one root of a tooth, if it is healthy, to be used as an abutment, as the palatal root of an upper, or the mesial or distal root of a lower molar. (Figure 2.) These surrounded by healthy tissue, give in most cases as equally good service as any single rooted teeth. We should, however, be careful in our diagnosis and treatment. Cause and result of treatment should be ascertained by the X-ray, and teeth which do not yield to treatment should be extracted. (See Figure 3.) Fig. 2. Mesial root of an inferior six-year molar, used as an abutment. The distal root of this six-year molar was amputated on account of chronic abscess. Above, radiograph ; below, model of the case. Fig. 3. Pathological conditions of the teeth. Radiographs of teeth and roots which had to be extracted on account of chronic abscesses and failure of root canal treatment. CLASSIFICATION 15 If roots or teeth are hopeless on account of their patholog- ical conditions or on account of their position or direction, we decide on their removal. (See Figure 3.) Certain crowns (and inlay abutments) are 2. Acid Mouth contra-indicated in an acid mouth; these are and Erosion half crowns with post, open-faced, and staple crowns. It is important to have all abut- ments extending under the gum, to eliminate as far as possible further attack of deca}^ and the dissolving of the cement, which is used for setting. A great many of the cases which we examine 3. Pyorrhoeatic have pyorrhoea tic teeth, and these are the Condition most difficult ones to diagnose and prognose. Some teeth usually have to be sacrificed, others can be treated in the regular way, and still others may Fig. 4. Pathological conditions of the mouth. Radiograph showing absorption of the alveolar process, caused by pyorrhoea alveolaris. be found sound. Kadiographs give us a good idea of the amount of absorption that has taken place in the alveolar proc- ess, and which teeth are strong enough for bridge abutments. (Figure 4.) When treating pyorrhoeatic teeth, the first and most im- portant is correction of the occlusion. Many teeth will tighten in a surprisingly .short time, if the strike is relieved to give them a chance to rest and recuperate. It is advisable in many cases to devitalize pyorrhoeatic teeth, and if they are to serve as abutments to cut them off. By extirpating the pulp of such a tooth, we increase the circulation in the alveolo-dental mem- 16 CROWNS AND BRIDGES brane, which then receives the entire suppl}^ of the dental ves- sels. Cutting these teeth off, even with the gum, will improve the condition for two reasons: first, it gives the teeth the im- portant surgical rest; and second, if used as abutments for the bar in removable bridges, it decreases the lever action. The next step to decide upon is, what appliance should be used. For phyorrhoea cases are recommended: {a) Bridges without bands. (5) Bridge splints. (c) Removable bridges. Fig. S. Pyorrhoeatic condition. Bridge splint. (a) Bridges without bands. If there is but little absorp- tion of the process with large and persistent pockets, or if bridges have to be made before the teeth can be cured, it is CLASSIFICATION 17 advisable to coiistrnct tliem in a manner Avliicli does not inter- fere with the scaling- and cnretting-. Therefore use abutments without bands, snch as inlays, lialf croAvns, bandless crowns, etc. (b) Bridge splints. These are used if mastication causes abnormal stress on the teeth, or on wandering teeth. Tlie process and gum has receded, and the free part of the tooth is out of proportion to the part that retains the tootl) in the Fig. 6. Pyorrhoeatic condition. Lower picture shows tlie condition before the treatment; a great deal of tissue has been absorbed, and the lever action on the part of the tooth extending out of the gum is great. Upper picture shows the roots cut flush with the gum and connected with a bar, which also acts to hold a removable bridge. socket, the lever action on tlie teeth in mastication has to be counteracted, the teeth have to receive a support to put them at rest, which is brought about by fixing them together Avith an appliance called a splint. Missing teeth can be replaced by adding them to the appliance. (Figure 5.) It is, however. 18 CROWNS AND BRIDGES important to keep in mind tliat a splint is not a cure for pyor- rhoea, bnt only a device to do two things: 1. Assist the healing process, allowing new bone to form, by giving the teeth a surgical rest. It may be used only as a temporary appliance. 2. To hold very badly affected teeth in place and pre- vent them from getting worse. These splints usually preserve the teeth for a number of years. A splint of that sort is called a bridge splint. It should, however, be so constructed that it does not interfere with prophylactic treatment b}^ the pa- tient, and pyorrhoea treatment by the operator, which should be continued at regular intervals. (Figure 5.) (c) Removable bridges. If a great amount of tissue has been absorbed, which we find necessary to fill in, or where there are but a few abutments, we find the most satisfactory restoration in a suitable removable bridge. (Figure 6.) The teeth are cut off flush with the gum, which does away with the lever action, and gives the remaining end of the root a much better chance. The roots are capi)ed and held in their position, this again strengthens them, while the stress of mas- tication is partly taken up by the saddle support on the gum. These appliances also have the advantage that the patient can take them out, and clean them, and what is of still greater importance there is easy access to the roots for prophylactic treatment. A great amount of tissue may be lost in some 4. Absorption cases, which on the lower jaw is of no of the Tissue great consequence, as the teeth do not show very much; but in the upper jaw, and especially in front of the mouth the tissue has to be replaced. To avoid ungainly long teeth we use saddles, replacing gum as well as teeth. Gum teeth can be used, or the bridge can be made in i)latinum, witli continuous gum. (Figures 7, 8, 9.) Often the gum over one tooth only needs to be restored; this can be accomplished by baking pink porcelain on a long plain tooth. In cases of much absorption, the restoration can be accomplished more satisfactorily with removable bridges, especially from the sanitary point of view. Fig. 7. Absorption of tissue. Model shows the absorption of tissue which has taken place on account of pyorrhoeatic conditions, and the replacement with a sum block. mi A A B Fig. 8. Absorption of tissue. Models show two bridges constructed to restore the absorbed tissue. A B Fig. 9. Absorption of tissue. A shows the length of teeth which would have to be used for a bridge without gum. B shows the gum block of the same case. 20 CROWNS AND BRIDGES B. AS TO OCCLUSION Mal-occlusion is a Yerj frequent complication in crown and bridge work. Therefore it is very important to study sucli a case witli the aid of models. In a case with normal occlusion there is, 1. Normal strictly taken, no tooth missing. However, Occlusion we will put under this head all the cases which need but restoration of a certain num- ber of teeth to give normal occlusion. These are among the jnost common cases of crowns or bridges. (Figure 10.) Fig. 10. Bridge case with normal occlusion. Upper six-year molar missing. Sufficient occlusion is a very convenient 2. Sufficient term for which we are indebted to Dr. Eu- Occlusion gene Smith, of Harvard Dental School. The occlusion is not normal, but the patient finds it sufficient, because restoration to normal occlusion would in- volve changes out of proportion to the result, on account of technical difficulties. In this class come cases of edge to edge bite, of over-bite of the lower molars and bicuspids, and some cases of mandib- ular, or maxillary protrusion. (See Figure 11.) CLASSIFICAriON 21 3. Mal-occlu sion Mal-occlnsion in llie adult can come from neglect of treatment for orthodontia in childhood, or can be acqnired in late life as '^closed bite" from loss of teeth or wear; as "protrnsion" of the maxillary incisors, caused by pressure from the lower ones; or as "tipping" or "elongation" of teeth on account of spaces, etc. We will subdivide these and consider them separately. Fig. U. Sufficient occlusion, edge to edge bite of the incisors, and over-bite of the lower bicuspids and molars. Fig. 12. Mal-occlusion. Spaces mesially and distally of the upper molar. The contact points have been restored by a hand-carved porcelain crown with cast base. 22 CROWNS AND BRIDGES (a) Lack of contact points. Teeth have the tendency to move forward if a space occurs from extraction (see Figure 12), but the contact point is not always restored entirely, and the space left is frequently a great source of trouble. But spaces between teeth are not necessarily clirectl}' due to the loss of a tooth. The teeth posterior to an extracted tooth move forward, but the tooth anterior to the space often moves back on account of force from the occlusion of the antagonist (Fig- ure 13.) Small spaces also occur from supra-numerous (Figure 14) peg-shaped teeth, and from insufficient restoration 1 ■ ;^ Fig. 13. Mal-occlusion. Space between the upper cuspid and bicuspid, latter as well as the lower first bicuspid, has been forced back. The of fillings and decay. Spaces of that nature ought to be filled in, either by contour fillings, inlays (Figure 15) with special extensions, crowns with large contour (Figure 16), or if the space is next to an abutment, the latter has to be constructed to restore the contact point. (b) Teeth tipped forward. (Figure 17.) Teeth which have tipped towards the space, or have been pushed out of vertical direction by force of a faulty bite, complicate bridge- work considerably. In some cases they can be ground suffi- Fig. 14. Mal-occlusion. Space between the lower cuspid and first bicuspid, caused by a supra-numerous tooth, which was not extracted in time. A B Fig. 15. Mal-occlusion. A, space between the six-year molar and second bicuspid caused by the extraction of the first molar. Space between the second and third molar caused by decay. B shows the same case with all the contact points restored. Fig. 16. Mal-occlusion. The space between the lower twelve-year molar and the second bicuspid was filled with gold crowns, sufficiently built out to get the contact point. 24 CROWNS AND BRIDGES Fig. 17. Mal-occlusion. The molar is tipped forward, so as to render the making of an ordinary bridge impossible. cientlj to bring them in line, but in extreme cases it is most always necessary to use special constructions, as: 1. TAVO-piece bridges with interlocking device. (See Figure 18. ) 2. Inlays with post for abutments. ( See Figure 19. ) 3. Kemovable bridges. Fig. 18. Mal-occlusion. Bridge with interlocking device to overcome the tip- ping of the tooth. For construction see Fig. 170. (c) Teeth elongated. Teeth wliich do not occlude, usually elongate, that is, they grow down from the maxilla, or up from the mandible. (Figure 20.) These have to be restored to normal length, either for looks or to get proper masticating CLASSIFICAriON Fig. 19. Mal-occlusion. Bridge with inlay abutments, — one way to overcome the difficulty of tipping teeth. occlusion, if the space opposite is bridged. AVlien tliey are ground down, and if the contact points are not lost, tliev can be filled with a well-carved inlay to replace the occlnsial sur- face. If the contact points are lost, as in teeth with narrow necks, it is best to crown the tooth with a suitable crown, or to cut a mesial-occlusial-distal cavitv for an extension inkiT. Fig. 20. Mal-occlu.sion. The upper bicuspid has elongated on account of the loss of the lower teeth. The bite has closed, making the condition worse. 26 CROWNS AND BRIDGES (d) Temporary teeth retained. Very often we find re- tained temporary teeth in persons of advanced age, and the question arises whether they should be used as abutments. A radiograph will give the desired information. (Figure 21.) Fig. 21. The right lateral incisor is a temporary tooth. The X-ray shows that the root is perfectly healthy, and strong for an abutment. The X-ray also ascertains the absence of a permanent lateral incisor. If the root is strong, firm and no absorption at the apex, there is no reason why it should not be a good abutment. But if we find the tooth i)artly absorbed (Figure 22), or if there is Fig. 22. Radiograph showing absorption of the roots of two temporary teeth, the central and lateral incisors. The cuspid has a strong, healthy root with no absorption. Be careful not to attempt to crown a tooth, when you en- counter a large opening and bleeding in the root canal. an impacted permanent tooth (Figure 23), these conditions should be carefully considered. A temporary root on which absorption has started is hopeless. If the corresponding per- CLASSIFICATION 27 A B Fig. 23. Showing unerupted cuspids under bridges, illustrating the importance of radiographic examination before constructing bridges. manent tooth is impacted and ill-placed wliile the temporary root stays, and no sign of absorption is shown in the radio- graph, we may remove the permanent tooth and use the tem- porary root. If there is a good chance for the permanent tooth to come down in good line, we may hasten its coming to the snrface by extracting the temporary root and making s[>ace for the permanent tooth by cntting away overhanging bone and keeping the space open. (e) Closed bite. The bite may be closed from the loss of the back teeth, and the wearing down of the front teeth. The A B Fig. 24. Mal-occlusion closed bite. The bite has closed to such an extent, the upper incisors have worn down so much, that the pulps were visible on the palatal side. A Ijefore, B after repairing the incisors with inlays and the sides with bridges. CROWNS AND BRIDGES upper incisors are worn on the cutting edge, or on tlie palatal surface (Figure 24), or are pushed out. If abrasion is the cause, the remedy consists in elongating the molars and bicus- pids with so-called shoes or with bridgework (Figures 24, 25, 26, A B Fig. 25. Mal-occlusion closed bite, the lower jaw. A before, B after treatment, filling the spaces with bridgework. 27 and 28). In some cases filling of the incisors at the palatal surface or gold inlays containing iridio-platinum is sufficient. However, loss of teeth and cavities more frequently produce this condition. The bite can be opened with bridgework or a plate. Fig. 26. Mal-occlusion, closed bite. Front view, before and after treatment. CLASSIFICATION 29 (f) Maxillary and mandibular protrusion. (Figures 29 and 30.) It is often desirable not only to adjust occlusion to im- prove mastication, but moreover to restore beauty and har- mony of the face. If after a certain age orthodontia has ceased to be applicable, cases of protrusion with irregularities of the front teeth can be corrected by bridgework in a more radical manner. The irregular teeth can be cut off and porcelain Fig. 27. Mal-occlusion, closed bite. These views of the left side show con- ditions before and after restoration, with bridgework to open the bite. Fig. 28. Mal-occlusion, closed bite. The right side of the same case (Figs. 24-28), same mouth, before and after treatment. 30 CROWNS AND BRIDGES crowns fitted at a different angle. In Figure 31 four teeth were replaced by a bridge of three teeth to get a better appear- ance and occlusion. (g) Wandering teeth. With this term we mean teeth which have been forced out of line either singly, or in groups, by mai- FiG 29 Mal-occlusion. The incisors have been pushed out on account of the closing bite. Models show the loss of the teeth in the upper and lower jaw, causing this condition. (See construction of bridges for this case. Figs. 202-211.) occlusion, and it is characteristic that they keep getting worse, moving further and further, pressed usually by a closing bite. (Figure 32.) Fig. 30. Mal-occlusion, mandibular protrusion. Harvard Dental School case. Before and after treatment in the Orthodontia and Crown and Bridge Departments. 32 CROWNS AND BRIDGES In these cases single crowns are contra-indicated ; sncli teeth have to be connected. Usually the roots have taken an oblique direction, and have to be cut flush with the gum; a bridge is then constructed with crowns extending down vertically, or the trouble is overcome by a removable bridge. (Figure 33.) Fig. 31. Mal-occlusion, maxillary protrusion, after treatment. B Model A, before; model B, A Fig. 32. Mal-occlusion, the upper incisors are projecting, before; B, after treatment. B A shows condition CLASSIFICATION 32, Fig. 2,Z. Mal-occlusion, wandering teeth. A shows case before treatment; the teeth have the tendency to move and are extending in all directions. B shows teeth cut off at the gingival margin, and connected with a wire, which holds them together, and also serves as abutment for a removable bridge. ( See con- struction Fig. 219-221.) Often it occurs that tlie maxilla seems to separate, produc- ing a space between the central incisors, especially if we have l)ridges on either side involving the centrals on each side. Cases of that sort can be drawn together and fixed with a staple, or a vault bar to tlie bridge. If spreading is prognoswl, in mouths with otherwise normal conditions, this can be cor- rected by inserting a staple. (I'igure 34.) (h) Irregularly arranged teeth. Regulating irregularities for sake of appearance is a task the bridge specialist is often ^^^ ^^^H Fig. 34. Mal-occliision. Spreading of the two central incisors. Case treated fifteen years ago. Radiograph showing condition today with perfectly normal pnlps. The holes for the platintim staple wire were drilled between vhe enamel wall and pulp chamber. Fig. 35. Mal-occlusion. A shows the position of the upper lateral, and cuspid. The lateral protrudes, the cuspid occludes lingually, and is twisted. B shows two Davis crowns in good occlusion, which have been attached to the roots. Fig. 36. Mal-occlusion. The one lateral incisor is absent, the front teeth are of irregular length, and have the tendency to move upward, on account of pyorrhoeatic condition. Fig. 9A shows four teeth which would fill the space for this case, which occurred after the absorption of the process. Fig. 9B is a gum block carved for this case. Fig. 8B shows the finished bridge with half-crowns and posts for abutments. f!f^^^^^H^^^^^^^^^^H^|B A B Fig. "ill . Mal-occlusion. . The case with very irregular teeth as shown in A, replaced by a bridge. In Figure B the same result might have been obtained with porcelain crowns, but the case was a pyorrhoeatic one, and two teeth had to be extracted, and the further moving of the teeth prevented by a bridge. 36 CROWNS AND BRIDGES confronted with. As a rule the teeth in question are the in- cisors and cuspids. The crowns of twisted, protruding or re- truding teeth can be replaced by porcelain crowns with normal and artistic appearance. (Figure 35). If the whole set of incisors has to be changed, we have a more difficult problem. As a rule there is lack of space for four incisors lined up in normal position, and it is hard to decide whether tliree incisors give a more artistic appearance than four very narrow ones. Each case is a study in itself and must be left to the good judg- ment of the operator. ( See practical cases Figures 36 and 37. > IV. PRELIMINARY TREAT- MENT OF THE MOUTH AND TEETH Before starting with bridgework the mouth should be put in general good condition. Sources of infection should be eliminated. First of all the teeth should be scaled and 1. Prophylactic cleaned and polished, which also gives ns an Treatment opportunity to select the right shade of the teeth. The next thing is to extract all roots and 2. Exodontia teeth which have been decided upon as worth- less. If there are pj^orrhoeatic teeth, these should 3. Pyorrhoea be treated; scaling and in some cases devital- Treatment izing is indicated. If they are to serve as abutments, they should be cut down at once to receive surgical rest. If all or most of the teeth are affected, a temporary splint might be applied until the treatment has sufficiently progressed. In some cases temporary plates are advisable to relieve the strain from the affected teeth. It is a much discussed question among crown 4. Devitaliza- and bridge workers, whether a tooth should tion of Healthy be devitalized previous to crowning in all Teeth cases. There are well-known writers who advocate devitalization in every case for various reasons. And there are also a great many other prac- titioners who can prove that pulps do live under crowns (see Figure 38), and think that it is not justifiable to remove a healthy pulp and take the chance of not even being able to thoroughly fill the root canals. Therefore the author 38 CROWNS AND BRIDGES leaves it to the operator to choose the wisest course and be gov- erned by the condition he is working under, and not by any law of one method only. Fig. 38. Radiographs showing cases where teeth have been crowned without devitalizing the pulps. The lower radiograph shows a right and left lower, one tooth extension bridge, both bridges in same mouth. The upper are bridges with live pulps in healthy condition, after fifteen years. Left lower radiograph shows a gold crown over tooth with live pulp, after twelve years. Right lower, gold crowns of teeth with live pulps after twenty-three years. The pulps of all the teeth involved in crown and bridge work sliould be examined as to their vitality. All the teeth with patholog- ical pulps as well as devitalized teeth should be examined with the aid of radiographs. These should be carefully studied, and usu- ally we can determine whether the tooth can be treated from the root canals, or whether surgical treatment is indicated. 5. Treatment of Teeth with Pathological Pulps (a) Treatment from root canals. Gases of pulpitis, acute alveolar abscesses, and sometimes chronic abscesses can be treated from the pulp chamber. The complete opening of the root canals is the most difficult part of this operation, and PllELIMINA R Y TRE/J TMENT 39 Cailiu'cs ill tliis, as well u.s in the proper tilling of tli«' canals, i^ive rise to the most coiHleinnable conditions. There is mucli more troiil)h.' cominn from insufficient root treatment tlian from the percenta[n^i' jjlaces before taking the impression. Select an Impression tray of proper size. Take a plaster impression of the bridge space and the teeth adjoining the abutments. For large bridges, take impression of entire upper and lower jaws. The broken pieces of a plaster im])ression and the traj should be thoroughly washed by running liot water over them, to insure proper replacement of all the pieces. (See Figures 58, 59, 60. ) Before placing crown abutments back into the plaster im- pression, make sure that the crowns are filled in with solder to reinforce the grinding surface, and that all flux is boiled out in acid. Place the abutments carefully in their places, also the broken plaster pieces, using sticky wax to hold them there. (Figure 204.) Varnish impression carefully. Fit pins or staples into the crowns, to prevent them from breaking off the plaster model. Pour impression with plaster and Portland, plaster and pumice, or some other good investment material. 4. MOUNTING GROWN AND BRIDGE CASES ON ARTICULATOR For large cases impressions of the entire upper and lower jaw should be taken, and the case is to be mounted on an anatomical articulator, using the face bow to get the right bite. (Figure 61.) Small cases should also be mounted on anatomical crown and bridge articulators. In placing the wax bite on the model, procured from the impression, care should be taken to cut away, with a warm spatula, all wax, which would interfere with the proper seating. The models are fastened to the articulators with plaster. After the plaster has set, soften the wax in warm water before opening the articulator. Protect occluding plaster teeth with tin-foil. 64 CROWNS AND BRIDGES Fig. 61. Case mounted on anatomical articulator by means of a face bow. 5. SELECTION OF TEETH Select the teeth according to the length of tl^e bite, the width of the abutments to restore the normal fullness of the face and other conditions caused b}^ the loss of teeth, such as a long or short lip, etc. Be sure that the color is satisfac- tory before grinding the teeth to place. With facings it is advisable to place a gold backing on one or two teeth, and try them in the mouth, as very often the backing changes the color. 6. GRINDING OF TEETH No matter what type of tooth is used, it is best in all cases to rough-grind the teeth into position first, and try them in the mouth in wax. Kearrange the teeth in wax, if necessary. (Figure 207.) Then only grind the occlusion. When facings are used, allow between the bite about 24 gauge thickness for backings of same. For box teeth such as Davis or Goslee type teeth, allow for thickness of box on gum, or saddle. (Figures 148 and 208.) To Enlarge Holes in Porcelain Crowns Very often we find it necessary to enlarge the hole in a detachable porcelain crown to make it line up with the post GENERAL TECHNICAL MANIPULATION 65 in tlic root. Tin's is Ix'st accoiiiplislKMl \\illi an S. S. Wliitc Number 1 Diamond Point, or with carborundum points. In either case use plenty of water and do not press too long and too hard at one place, as this will spoil the cutters or stones. 7. BACKING OF TEETH When teeth are perfectly ground and waxed to position to the abutments, and the spaces on to tlie model, varnish or shellac the front of the plaster model, and pour a plaster core or jacket over same. (Figures 65 and 208.) Boil out the wax and observe whether the distance between the teeth and the abutments, between the saddle or the gum, is sufficient for the gold backing, or box, and reinforcement of the same, to get sufficient strength. If the distance is not right, now is the time to correct it, by grinding away from the back of the tooth. This is the i)lace to give strength to the Ijacking or the box. ( Figure 208. ) Now remove the teeth from the core and swage the backing or the box. Cut the first backing of sufficient length to reach from the cutting edge to the gum line. When the teeth are in the core on the model, we can cut and fit all the backings correctly, where they should reach. This makes the soldering simple and gives more strength. The first backing should be 24 karat 31 gauge. Anneal the gold, punch holes first and swage backing to the tooth. (Fig- ure 62.) Do extend, but do not have backing bent over the A B Fig. 62. A, Facing with single; B, Facing with double backings. cutting edge. Many facings are weakened or cracked, when swaging the backings. When swaging, make sure to have the facing well supported in the cup of the swager, from the cutting edge to the labial cervical margin. Examine the facing for defects closely before soldering. 66 CROWNS AND BRIDGES 8. REINFORCING OF BACKINGS Cut a backing out of 26-gaiige 18-karat gold plate to extend from the pins to the cutting edge over the first backing of jDure geld. Do not attempt to swage this second 18-karat backing on thin or narrow teeth, as these facings are liable to crack. Bend 18-karat backing in such cases approximately with pliers. Remove both backings from the tooth and unite them by flowing 18-karat solder in between so it will shoM' at all edges. (Fig- ure 63.) Boil in sulphuric acid 20%. Replace backings to the Fig. 63. Soldering the two backings in the flame. facings and burnish it around the pins with a hollow burnisher. Do not cut or split the pins. After soldering the backing to the pins, either in sections or in one soldering with the abut- ments, file the backing at a right angle to the level of the facing. It is advisable to reinforce Goslee or similar tooth boxes also with 18-karat 26-gauge plate, to strengthen the back- ing over the pin (Figure 139B) at arrow-point b, and to pre- vent polishing through at the weakest point of the box at arrow- point A. If the box is not reinforced, at b the post with the thin backing often breaks away, and at the point A the solder GENERAL TECH MCA L MANUAL LATION 67 does not always covit sufficiently to prevent a hole to be pol- ished tlirongh. The IS-karat extension backing prevents both of these events. This same reinforcement is also useful "when using a Davis type crown as an abutment. (Figure 131)10 i. The Goslee platinum or gold ])Ost with shoulder will also prevent the post from breaking away from the box. Other use- full suggestions in box construction for Goslee teeth are fur- nished by the dealers of these teeth. The most commonly used gold solders in l)ridgework are the 22-l?;arat, 20-karat, and IS-karat. The higher karat gold is used to prevent discoloration of the joints of bands, and all metal crowns, and also to prevent refiowing. For example, use a higher karat gold solder for the soldering in constructing abutments, and the lower karat (IS- or 20-karat as a rule) to unite the abutments and dummies. 9. TO PREVENT THE CRACKING OF FACING When setting up a bridge case Avitli facings, allow small spaces between the teeth, so that they do not touch each other ; this allows for expansion of the porcelain caused by the heating of the case, and when soldering. Take an iron or german silver band about ^ inch high and invest the bridge into this (Figure 208). Have the investment of small size and expose by cutting away the investment, the surface to be soldered as much as pos- sible. Remove all wax by pouring boiling water over it. Do not hurn the wax out over the flame, because this will make the gold surface unlcean. Examine the invested bridge once more before heating, to see if any part of the porcelain is exposed, where the backing should extend; cover this place with a thin piece of platinum or pure gold plate. Gold-foil is also very useful to cover such exposed places; be sure to pack the foil thick enough, so that it will not burn away under the flame when soldering. Large spaces such as between tooth boxes and saddles are best packed with Alexander gold; this gold will pack in like wax, and suck up the solder. Tooth boxes on saddles are best invested, and soldered, leaving both the front and back open. (Figure 64.) This enables us to solder from both sides. Large backings for gum blocks to be soldered to 68 CROWNS AND BRIDGES gold plates or saddles are also best invested in the same way. Heat tlie case over a suitable flame slowly, so that the porcelain will not crack. Always let the bridge cool slowly after solder- ing, for the same reason. A Fig. 64. Showing a Goslee tooth saddle bridge invested ready to solder. Figure A shows the back of bridge, Figure B the front of bridge open from both sides, and partly packed with Alexander gold. This kind of investment permits perfect soldering on both sides. When ready for soldering, flrst test if the case is dryed out and hot enough to solder by sprinkling powdered borax on the metal surface. If the borax puffs, or boils up, the case is ready, otherwise heat longer; add the borax, and also solder, GENERAL TECHNICAL MANIPULATION 69 and place the case on the sohJeriii^^ block so that tiie soldering does not interfere with the laws of gravity. Tlie solder will flow downwards and also towards the hottest part, therefore tip tlie investment accordingly, and apply the heat where you want the solder to flow. A poker, such as a broken excavator, will also help to lead or push the solder when melted to the right place and is very lielpful. Keep sprinkling dry borax during soldering to tlie bridge and sohler as needed. Soldering fluids should not be used on a hot case for two reasons : first, if used on backings witli facings, tlie moisture and cold may crack the facing. Secondly, applying a fluid to hot metal with a brush, the end of the brush will burn, and leave a carbon deposit that will prevent good soldering. In soldering gold bands, put the soldering fluid on the surface when the metal is cold, then place the solder and melt in the open flame, or with blow-pipe. 10. SOLDERING BRIDGE IN SECTIONS To overcome contractions on bridges, it is necessary to solder the dummies in sections, then replace these soldered sec- tions on the abutments and unite the whole. (Figure 65.) Fig. 65. Showing a full upper bridge. The teeth have been soldered together in three sections to prevent contraction. Case is ready for final assembling and soldering to the bridge abutments. 70 CROWNS AND BRIDGES 11. CASTING The introduction of pressure easting by Taggart, has so revolutionized many methods of operative dentistry, crowns and bridgework, that we may call its introduction the most remarkable period of modern dentistry. In crown and bridge work, we can now use inlays with posts, as abutments, cast vault and sub-lingual bars, cusps to crowns, dummies for sani- tary bridges, saddles for saddle bridges, etc., etc. Though perfect results can be obtained Avith small and me- dium sized pieces, it is not practical to undertake too com- plicated and large castings. For example, it would not be advisable to cast too many dummies to the abutments, because these would be drawn out of position by contraction. Expe- rience and good judgment must guide the selection of the method. Like with all new inventions, we can only find its real usefulness by experiments. So also in the castiiig process, the pendulum swung over to one side ; first everything that we formerly would solder, had to be cast : small and large pieces of bridgework, with and without teeth, upper and lower, full, and partial gold plates, with or without teeth, clasp, bars, boxes, saddles, dummies, croAvns, etc., — everything had to be tried and tested before the pendulum swung back the other way, and we are now satisfied that, after all, swaged crowns, swaged cusps, swaged plates and teeth soldered to same, are still su- perior to casting in many cases, with the exception of small cases, such as the casting of single crowns, tooth boxes, saddles, sanitary bridge supplies, vault and sub-lingual bars, inlays, etc. I prefer to swage and solder all large pieces as of old. To get perfect results we have to watch carefully all the small details connected with the making of the wax pattern, the investing, setting, drying and heating of the case, and this is of greater importance than the use of any special make of casting machine. Beautiful results can be obtained with the simplest as well as the most expensive casting machine, and whether using vacuum, steam, centrifugal power or gas pres- sure. A paper reviewing the pressure casting, compiled from the recent "American Literature" has been read before Section V at the Sixth International Dental Congress, London, 1914, and a report of this can be found in the "Items of Interest," GENERAL TECEINICAL MAKIPLLATIOS 71 Volume XXXVI, No. 10, October, 1914. A icporl of Dr. Otto- lengin's "Review on Coasting" is to be found in the ''Items of Interest," Volume XXXVI, No. 11, November, 1014. TECHNIQUE Wax form The wax form is either carved on the anatomical articulated model, or in cases of inlays, by the direct (from the mouth), or preferably by the indirect method. In I In- latter «-asr an amal- gam die is made. Taggart's wax, also Kerr's blue wax, is recommended. When carving, special pains should be taken to reproduce nature as far as possible. All the cusps, grooves, fissures, and sulci should be imitated from extracted teeth, or a good plaster model of perfect teeth. Not only should the casting be carved to occlude properly, it should also aUoto nor)iial lateral moHoiK as produced in mastication. The carved piece is then smoothed with alcohol, and a sprue wire, of the size of an ordinary pin, is placed in the most bulky part. Place the sprue wire into the hole in the sprue and hold it with wax. Investing The process of investing the wax is very important, and all small points should be carefully observed to get the most per- fect results. Taggart's special investment compound is highly commen- dable. Use it as follows: Fill the large cup of the balance scale that comes with the box with loose powder and scrape off level with a straight plaster spatula. Place the weighing device on the fulcram and with a water syringe fill the small cup until it exactly balances ; cover the powder and pour the water into a clean plaster bowl, now add the powder. Spatulate for one minute, then jar and rotate the bowl for two minutes more. On account of the fluid condition of this mixture this prolonged manipulation permits all the air and gas bubbles to come to the surface. The inlay should then first be painted with the investment material, and the balance is poured into the ring in such a manner as to permit it to trickle down the inside of the ring. Do not hurry the work; there is a period of at least eight minutes during which the material is workable. 72 CROWNS AND BRIDGES Let the investment harden for about twenty minutes, and then place it over a small flame, heating it up slowly. As soon as the wax has burnt out, cast, or let the flask cool and cast later. The twenty minutes heat gives a better surface than if heated too long, and casting in a cold flask prevents feathers on the casting. Gold Use coin gold for inlay abutments, or platinized gold, add- ing 2|% platinum to the j)ure gold. Use 18 or 20-karat gold for parts of bridgework. Better still are gold alloys, after Weinstein's formula. 1. SOFT ALLOYS FOR INLAYS, ETC. (Melt by nitrous oxide or ordinary blow-pipe) Pure gold 60-90 parts Plate Number 2 10-40 parts according to hardness desired. 2, HARD ALLOYS FOR BRIDGEWORK (For nitrous oxide blow-pipe) Pure gold 80.0 parts " platinum rhod 8.5 " " palladium 3.5 " " silver 2.0 " " copper G.O " (For gas and air blow-pipe) Pure gold 80.5 parts " platinum rhod 6.5 '^ " palladium 2.5 " " silver 2.5 " " copper 8.0 " 100.0 12. POLISHING OF CROWNS AND BRIDGES In order to attain the highest finish on a crown or bridge, care and patience must be used in properly filing, stoning and sand-papering before applying felt cones and brushes for the final polish. No matter how smooth your soldering appears, all soldered surfaces should be stoned. In spite of boiling in GENERAL TECHNICAL MANIPULATION 73 acid, some borax and also a skin-like porous coverinj^ of these surfaces is not always removed by the acid. Carborundum stones in the dental engine or lathe attachments are the handi- est in reducing gold and getting smootli surfaces. While rub- ber carborundum wheels are best to use for the inter-dental spaces, between crowns and near cutting edges, sand-paper disks on a mandrel are also of great help. Before polishing, always stone and finish the deep fissures and the inter-dental spaces first. These inter-dental or so- called wash spaces can be reached best by applying pumice and water, or tripley rubbed on twine. Hold these with the left hand, and with tlie right hand work the bridge against the twine in a quick up-and-down motion, until the desired result is obtained. Now polish the large surfaces with pointed or flat felt cones, pumice and water, tripley, or otlier polish; then go over tlie entire bridge with a brush Avheel until all the scratches are removed. Wasli all tlie pumice off and apply whiting or rouge with a soft ])rush or polishing wheel, then wash bridge again with warm water, and gold plate same. 13. GOLD PLATING OF CROWNS AND BRIDGES It is of great importance to gold plate soldered crowns, also all bridges. The deep fissures, the soldered joints, such as between the crowns and the dummies, and the gold in the inter-dental spaces show the first effect of oxidation in the mouth. Large surfaces and especially masticating surfaces are kept bright in polish and color through the constant rubbing and friction caused by the masticating and cleaning process. When a bridge is properly gold plated with 24-karat gold plate, we have a piece of work which is of uniform color, and the plating will protect all the deep fissures and soldered joints from discoloration and oxidation for many years. There are various plating outfits offered for sale on the market. How- ever, it is very simple and easy to make your own apparatus, which will do good service. Here is one I have used for many years. (Figure 66.) Use the following solution in the jar : Chloride of gold 30 gram Cyanide of postassium 60 " '^^t^^ 8 ounces 74 CROff'NS AND BRIDGES Fig. 66. Gold-plating outfit, of simple construction, for 110-volt direct current, using a 110-volt '16-candle power lamp and one 220-volt 32-candle power lamp to reduce the current. (See page 73.) 14. FITTING OF BRIDGES IN THE MOUTH AND WEARING THEM FOR A DAY OR TWO In fitting large bridges we often find that the finished bridge will not go in its proper place, or as we may term it, is not seated. This may be due to some carelessness in putting the abutments in their proper places in the plaster imj)ression, or it may be caused by a broken off abutment on tihe plaster GENERAL TECHNICAL MANIPULATION 75 model, and when tliis iil)ntnient was not put back in tlie exact position, where it behjiioed. Anotlier cause rnay be that the bridge has contracted in the final soldering. (See Figure 65.) If it should l)e necessary to refit the bridge, cut some of the abutments off, place them in the mouth, take another bite, and impression, and resolder. But these mechanical defects of tlie bridge aboveiiientioned, are not tlie only causes that may prevent a bridge from going into its proper place. One of the commonest causes is the side shifting or moving of the teeth or roots, to which tlie abutments have been fitted; in such cases it is advisable to let the patient wear the l)ridge uncemented for several hours, or even twenty-four hours, during which time the teeth will readjust themselves to the bridge. If the teeth or root canals liave not been lined up to prevent the bridge from getting into place, it is best to start all over again and use more care. Figure 201 shows an instrument of great value for sucli cases. 15. CEMENTING OF CROWNS AND BRIDGES Never try to cement a crown or bridge until the same has been tried and is correctly seated. Make sure that the apical end of the roots are correctly filled. It is important to know the working qualities of the crown and bridge cement used, its color effect and especially its setting period. Dry the abutments of the bridge, and wherever there is a saddle or deep inter-dental space, coat these places Avith a thin film of vaseline. (The vaseline will prevent the lodging of cement at these places after the bridge has been cemented.) Paint the gum around abutments with camphor phenol, or a 20% solution Novocain, and dry all roots and teeth which are used for abutments by wiping them off first with alcohol and then applying warm air with chip blower or compressed air. This overcomes the pain so often caused by the cement. Place cotton rolls and nap- kins around the teeth to be crowned. After the assistant has mixed the cement and is filling in the different crowns, the operator should, with a suitable instrument, fill cement in the root canals which are to receive post crowns. Do not mix the cement too thick, fill the crowns even full, as this will pre- vent the arresting of air, and act as a lubricant to slide the crowns into place. The bridge must be held into place until 76 CROPFNS AND BRIDGES the cement is set. If the operator cannot hold the bridge in position with one hand while he burnishes the metal caps to place with the other hand, before the cement sets, an assistant should hold the bridge. Color of cement important The color of cement is of great importance when open-faced, staple, half crowns, with post or inlay abutments are used. If a brown or gray cement is used in such cases, it mil often change the color of the tooth. To prevent this, a light yellow cement is preferable, which will sustain the natural color of the tooth. 16. FINAL ADJUSTING OF OCCLUSION The correct occlusion of a crown or bridge is most impor- tant, as the comfort, the service, and life of the crown or bridge depends on this to a great extent. Have the patient bite in the various ways which the move- ments of the lower jaw permit; ascertain the hard striking- places by the use of carbon paper; grind them carefully witl; a suitable stone. Be sure to clear the cuspids of the lateral bite, as these are the ones that are most severely affected. In a general way follow the directions for adjusting the bite of a crown or bridge as you would for setting up teeth on an ana- tomical articulator. 17. INSTRUCTION TO PATIENTS Patients frequently experience more or less difficulties with new bridges, especially if they have been without teeth for a long time. If large bridges are jjut into a patient's mouth, they feel, as they often express it, "all teeth." The tongue which was used to a large space, taking up the room of the lost teeth and extending even into the vestibulum oris, finds itself suddenly restricted to the cavum oris proper. It often takes several weeks before the tongue gets used to its new environ- ments. Mastication is another feature which has to be considered. If many of the molars and bicuspids have been missing, the patient either masticated with the front teeth, or swallowed GENERAL TECHNICAL MANIPULATION 77 the food uncliewed. JJotli liabits liave to he corrected. The patient ought to be instructed to use tlie hridj^e and to masticate each mouthful of food properly. In tlie l^egiiining- this may trouble them, as tliey may not have used that side and the teeth for a long time. But gradually the need is supplied by nature, the circulation will increase in tlie alveolo-dental membrane and the tissues surrounding the teetii will be strengthened until they are all able to fulfill their requirements. It is of great importance that tlie occlusion should be adjusted for proper masticating antagonism. Anatomical articulators should be used for the co)istrnctioi) of all hrklrjes, and the teeth should be readjusted in the mouth l)efore and after the bridge is set. 18. CARE OF BRIDGES Bridges should be properly cared for by the patient, and should receive regular attention by the dentist. Fixed bridges can be cleaned with the toothbrush, dental floss and cleaning tape, in combination with a proper tooth paste. Removable bridges are easy to keei) clean, that is, the bridge itself; the abutments and gum, however, should not be neglected, and re- ceive careful brushing. Brushing of the gum is important to stimulate the blood circulation. Massaging the gums around removable bridge abutments with cotton rolls in a Kuroris holder is highly recommended. VII. SINGLE CROWNS Whenever there is a croAvn of a tooth missing or badly decayed, with its root in good condition, or with a root which yields to treatment so as not to be a source of infection, it is safe to crown, providing the bite is favorable. There are different types of crowns which can be nsed to replace such a tooth, and they are made for different conditions. The type of crown which comes nearest to the ideal condition, without tak- ing a chance as to its practical value, should be selected. The ideal crown has the following qualities : Clean surface. Not irritating the gum. Esthetic appearance. Kestoring occlusion. Kestoring contact points. ALL PORCELAIN CROWNS These are the most ideal crowns. Porcelain is the cleanest material and gives the best effect. If propertly fitted, porcelain crowns are most favorably received by the gum. TYPES OF ALL PORCELAIN CROWNS 1. Jacket crowns. 2. Detached post crowns. Hand-carved crowns. Stock crowns. 1. JACKET CROWNS Crown I. This crown can be used for a devitalized tooth, as well as for a tooth with a live pulp; it encloses the part of the tooth extending over the gum like a jacket, therefore the name. Its use is largely to restore malformed, peg-shaped, pitted, or erosed teeth, but can be used to replace almost any tooth in the mouth, if tooth or root is rightly trimmed and built up. SINGLE CROfrNS 79 Preparing of tooth To XJrepare the tootli for a jacket ei'o\\ n, cut down the tooth to pi'ocui'e a coiK^-shnjK' A\'illi shonIure 74.) Fig. 74. Steps of making porcelain baked crown, using platinum base. Root preparation Prepare root as for Crown III, A or B. Fitting of post into canal and making of cap Fit an iridio-platinum post into root canal of same size as root reamer used. Remove post and fit a cap of platinum plate (32-gauge) over ground surface of root, as following: Punch a hole in the platinum plate over the opening of the root canal, and push the previously fitted post through the plate into position; leave the post projecting over the plate, withdraw and catch with platinum solder or 24-karat gold plate or foil. Eeplace to root and burnish the plate well over the edges of the root, holding it in place with a suitable instrument, and press- ing the metal with a shoe-shaped gold plugger on to the root, trimming and conforming the cap until perfectly seated. SINGLE CROl^NH 89 Making of crown Take a wax ])ite and plaster impression with tbe cap and post in ]iositioii. T'ast the iiiii)i'essi()n with cap and post, usiii^ plaster and I'ortland, or other suitable investment. Grind a facing to the articulated model. Bend the pins of the facing to the platinum post. Wax the facing to the cap and post and invest. Boil the wax out and heat it carefully. Solder tiie facing and tlie cap to the post witli platiiiuiu solder or pure gold plate. When cool, remove the jjlaster and fill in with medium or high fusing porcelain the back of the soldered facing and cap. Keep tapping to bring tlie iiioisture to the surface until perfectly dry. Set the crown on a broken clay pipe-stem and bako. Bake it with a slow heat up to fusing point and again cool down slowly. Add more porcelain if necessary, and bake again until the required shape is olttained. Cementing of Crown Cement to the root in ordinary manner. 2. PORCELAIN GROWN WITH CAST BASE If the root is decayed under the gum line, and a band is impossible or undesirable, a cast base will often meet the re- quirements to obtain good results by the direct or indirect methods. Direct Method. (Figure 75.) Root preparation Remove all decay from the root and reduce it with burs, stones and root facers, till it extends slightly under the gum margin. Open the canal with a Kerr broach and Gates Glidden canal drill and enlarge it with a root reamer. 90 CROWNS AND BRIDGES Fitting of post and making of crown Fit an iridio-platimim post as liii»li toward the apex as possible. Eough grind a detachable post crown of suitable size, and color, so that it will fit close to the labial portion of root end, leaving a V-shaped space between crown and root end on the palatal side. (Figure 75.) Fig. 75. Porcelain crown with cast base. Direct Method. Vaseline the base of the porcelain crown. Warm the post and form inlay wax around it. While wax is soft press the post and wax into the canal and press the vaselined porcelain crown into position. With a warmed instrument trim the excess wax so that it will be flush with the sides of the root and crown; when the wax is chilled carefully remove from the root, first the crown, and then the post with wax attached to it. Attach sprue wire to the thick palatal part of the wax. Invest and cast with 22-karat gold to the post. Kemove any imperfection from casting and fit crown to casting and to root end. Cement porcelain crown to base and polish. Cementing of Crown Cement then the crown to the root in the usual manner. Indirect Method. (Figure 76.) Root preparation and fitting of post Prepare root as for direct method. SINGLE CROf^NS 91 Fitting of post Fit post as for direct method, tlien cover the fitted post with a thin film of wax or paralfiiie, and i>ress it into the root canal. Impression Select a copper hand of suitahh' size and fit it over the pre- pared root. Take an impression of the root by forcinj^ a Kerr modelling- componnd stick, the end of whicli has he<^n softened into the band. Fig. 76. Porcelain crown with cast base. Indirect method. Take an impression of the adjoining teeth, and a bite to make an articulated model. Trim and shape the die cone-shape and place it into the impression, same as placing a crown abutment back into the im- pression, then make an articulated model, from which the die can be removed. Making of crown Select a porcelain crown of suitable color. Shape it to fit at the labial or buccal part of the neck, also to be in contact 92 CROWNS AND BRIDGES with the adjoining teeth, and to occlude properly. Grind the porcelain crown at the palatal side so that there is a large V- shaped space between the root and the base of the crown. Eemove the post from the amalgam die, vaseline the die as well as the base of the porcelain crown. Take some inlay wax which has been heated previously, and stick the post to same, then place it over the die, pressing the porcelain crown in position while the wax is soft. Let the wax cool and remove the die and crown from the model. Take a warmed instrument and trim the wax flush with the model and the crown. Place a sprue wire into the lingual part of the wax where it is thickest. Eemove the porcelain crown and then draw the wax with the post from the die. Invest and continue as for the direct method. G. BANDED CROWNS These are a step removed from the ideal, as a band, even if fitted very accurately, is irritating to the gum and therefore more or less objectionable. For bridge abutments this is, how- ever, very often required to get strength, and it has its obvious advantages for weak roots. Platinum is the ideal metal for root bands and caps. I. Base for Banded Crowns Direct Method 1. Soldered caps. 2. Burnished caps. Indirect Method 3. Swaged caps. n. Supplies for Banded Crowns A. Banded crown with facing. B. Banded crown with detached post crown. C. Banded crown with Goslee tooth. D. Banded crown with Steele tooth. SINGLE CROli'NS 93 I. Base for Banded Crowns Direct Method 1. SOLDERED CAP Root preparation Remove all decay from the root. Grind the labial portion down below the gum margin while the palatal portion may be left longer. Cut the sides of the root parallel, removing all enamel by the use of enamel cleavers, knife edge stones, Evans" tissure burs, or all combined. Oj^en the root canal Avith Kerr broaches and Gates Glidden drills and enlarge with Davis root reamer. Making of cap Measure circumference of the root below the gum margin with a wire in dentimeter. (Figure 77.) Use platinum plate or cut a strip of 22-karat 30-gauge gold plate with sides par- allel of the length of the wire. File the ends so that they form a perfect joint when bent to a band. (Figure 77, ) Fig. 77. Steps for making of band for soldered cap. Bind around this band an iron binding wire to hold the joint together while soldering. Put wet flux outside of the joint and a small piece of 22-karat solder on inside. Hold it in the flame and flow the solder, uniting the joint. Fit the band on root, trimming the cervical edge parallel to the margin of gum and filing it to a bevelled edge. See that it extends slightly under the gum margin. 94 CROWNS AND BRIDGES Trim the top of the band so that it is flush with the top of the root. Burnish a piece of 34-gange 22-karat silver alloy gold plate over the top of the root and band. Remove band and fit the burnished piece to place, soldering it with 22-karat solder. (Figure 78.) Trim the overhanging edges. Cut a hole Fig. 78. Fitting of top to band and soldering post. through the top, opposite the root canal, with Dr. Hovestadt's special punch (Fig-ure 79) and burnish well into the root Fig. 79. Dr. Hovestadt's special plate punch. canal. Push the iridio-platinum post through the cap into the root canal, allowing a short piece of the post to extend from cap. (Figure 80.) [2i a uvn V v ■ — ■ — '^- Fig. 80. Showing the use of the plate punch. SINGLE CROfi'NS 95 Take a small plaster impression to secure the relation of fehe cap and post. Remove cap and post and fit into i)lace in the impression. Make small model of impression material. When snfficiently hard break the impression away and solder with 22-karat sol- der. Sticky wax or Kerr impression sticks may be used in- stead of plaster im])ression l)y lieatin*; the end of the stick and pressing it against the extending post and cap. Chill and withdraw. Invest and solder as above. (Figure 78.) Flow solder first on the post then draw it to the cap ; other- wise it would flow over the cap only. Platinum plate and posts for all kinds of hases in croirmrorl- cannot he surpassed and (live the best satisfaction. 2. BURNISHED CAP ^Crown VII) Root preparation Cut the root level to the gum line, then bevel all sides of it below the gum, leaving the centre around the root canal opening high. (Figure 74.) Making of cap These caps can be made of platinum plate 34 gauge, or 32-gauge pure gold plate. Take a piece of sufficient size to cover the top of the root and punch a hole through its centre with special punch. (Fig- ure 81.) Place this over the root, and push a previously Fig. 81. Hand-burnished top with post. (Finished crown.) prepared good fitting post through the hole into the root canal. Flow a little sticky Avax connecting post and plate (small cot- ton pellets saturated with sticky wax are very practical for tliis purpose) and withdraw from the root. Invest and solder the post to the plate. To determine the exact out- line of tlie root and to trim the plate or cap accordingly, 96 CROWNS AND BRIDGES take a piece of temporary stoj)ping, press it flat and punch a hole through the middle and lay this over the back of the plate. Heat all and press it on the root, chill and withdraw it. Trim the plate according to the outline of root on the temporary stopping. Then remove the temporary stopping and return the cap to the root, holding the cap in position with a suitable instrument with the left hand, and with the right hand form the plate to the shape of the root by working with a cerated instrument from the post towards the periphery. A shoe-shaped gold plugger is ver^^ good for this purpose. Hand or automatic mallets are also very practical to drive the plate to place. The old hand mallet and shoe plugger is, however, preferable to any other method when fitting a platinum plate to the root. Hold the plate in position with the left hand, the right holding the long plugger; the assistant is to deliver two blows at each position of the shoe-point. A cerated instru- ment lays the metal down smoother and quicker than a smooth flat instrument or burnisher, which will thin out and wrinkle the metal. Kemove the burnished cap and trim the edges smooth. Indirect Method 3. SWAGED CAPS Root preparation Prepare the root, removing all decay, and trim it slightly below the gum margin, leaving its centre high. (Figure 82.) Fig. 82. Steps showing the making of swaged root caps (or coping). SINGLE ClWI^yNS 97 Making of cap Fit an iridio-platinuin post into tlio root canal as ]iijj;li toAvard apex of the root as possible. Kemove post and fit a copper band loosely around root. Shape a Kerr impression compound stick to fit the inside of the band; soften the end of the stick and press it into the copper band on the root. (Figure 82.) Chill and remove the compound and band and cast a plaster model of the root end. After the plaster has hardened, remove the compound, lengthen the outline of the root end on ])]aster model by trim- ming the plaster. Powder and press this plaster model of the root into soft moldine, pour Melotte's metal into tlic impression thus gained. (Figure 82.) Swage on tliis metal die a 32- or 34-gauge platinum plate to form a cap or coping. (Figure 82.) Trim and fit the coping to the root in mouth. Eemove and punch hole through coping with Dr. Hove- stadt's special punch. Place the coping back to the root and force the fitted post through the hole in the coping into the root canal. (Figure 82. ) Dry the coping and the end of the post and place cotton pellet saturated with sticky wax over them to secure the rela- tions of the two. Withdraw the coping and post carefully from the root and invest. Solder the post to the coping with a small piece of platinum solder or pure gold. Boil in acid. The swaged cap or coping is now ready to receive its mount. II. Supplies for Banded Crowns A. BANDED CROWN WITH FACING (Richmond) Crown VIa, Crown VIIa, Crown VIIIa Making of model After the cap and post are made, by any of the Methods VI, VII, VIII, place the cap on the root. Take a wax bite and plas- ter impression and stick the cap and post in place into the im- pression. Make an articulated model, using an anatomical crown and bridge articulator. 98 CROWNS AND BRIDGES Making of crown Grind a suitable facing to fit the cap and bite, allowing a space of 24: gange between it and the occlnding teeth. Bevel the back of the cntting edge of the facing. Make double gold backing and attach them to the facing. (Figures 62, G3. ) ^Vax facing to cap and post and invest. Boil the wax out and heat it slowly. Solder with IS- or 20- karat solder. When cool, remove tlie investment, boil in acid and polish. (See Figure 83.) Fig. 83. Banded crown with facing. B. BANDED DETACHED POST CROWN Crown VIb, Crown VIIb, Crown VIIIb Making of model Fit a cap after Methods VI, VII or VIII, but let the post extend above cap far enough to retain a detachable post crown. Take a bite and impression with cap and post in place. Make an articulated model. Grinding of crown to cap and post Select a proper sized detached post crown. Eough grind the crown as nearlj^ perfect to the gold cap as possible, then fit Fig. 84. Soldered cap with detached post crown. SINGLE CROONS 99 it accurately In riibbiii;^ the <4r(>iiiila<-eineiits. If the teeth and roots, wliicli are to serve as jilmtiiiciils, are in a healthy condition, or if they can be put in siicli ;i condition by treatment, if tlie occlnsion and the (listancc lierwccii the gnm and the antagonizing- teeth is of snfticient widtli. then a fixed bridge will be found most satisfactory IihIimmI. A. ABUTMENTS FOR FIXED BRIDGES Bridge abutments should be selected acccjrding to their practical value and strength, technical conditions, i)i-ophyhirtic and estlu^tic properties. It is of greatest im])ortanf(- to select the right kind of abutments, and a careful study should be made of the prevalent conditions. Here at the start is the op- portunity for the operator to show his ability and foresight, which will lead to success. The lasting quality of a bridge depends greatly upon the choice of the abutments. It would be unwise to use open-faced, staple or Iialf-shell crowns witli posts in a mouth with acid conditions, because these would not last very long, the cement would dissolve and the teeth decay at the exposed surfaces. In a close bite Ave should not use Goslee teeth, Steele posterior or Davis croAvns, as they could not be made strong enough. In pyorrhoeatic conditions, bands under the gums should be avoided, and the foremost thought in constructing the bridge, should be the possibility of propliv- lactic treatment of the abutments and the adjoining teeth. Some of the bridge abutments have already been described in the previous chapter on single crowns; they will therefore only be referred to here, while abutments which have not yet been spoken of, will be described in detail. INLAY ABUTMENTS 1. INLAY WITH POSTS AND M. O. D. INLAYS (Abutment I) Inlays for bridge abutments should be cast with platinized gold. They should invariably have posts in the pulp canals 120 CROWNS AND BRIDGES with the possible exception of M. O. D. cavities (mesial, occlu- sial, and distal cavities) . All cavities for inlay abutments shonld be sufficiently cut so that the arold extends well towards the buccal and lino'ual Fig. 117. Tooth preparations for inlay abutments. surface, this gives the patient a chance to keep the margins clean. The cervical margin of the inlay should extend below the gum. Impression Inlays can be made by the direct, but preferably by the indirect method. In the latter method we take an impression with a small tray, a seamless copper or aluminum band. Fill Fig. 118. Steps for bridge with inlay abutments. it with Kerr's modelling compound (stick form), and press it over the tooth or place the ring over the tooth, pressing the softened end of the modelling compound stick into it. Let it cool. The wax pattern is then roughly shaped in the mouth, by letting the patient bite into it, and also perform slight lateral masticating movements. Take also a wax bite of cavity, and the adjoining teeth in case an articulated model is wanted. For Taggart's wax use the following method: FIXED BRIDGES 121 Mount the piece>s of wax on lon^- pins tliat are stiir-k into a large round piece of cork to fit the top of a water glass. The glass is filled with hot water. The heat of the water may be tested by holding a piece of wax in same, and should not be quite as hot as to turn the wax pale. The pieces of wax mounted on the pins of the cork are allowed for a few minutes in the liot water, and may then be found just right to press into the tootli cavity or metal die. Kerr's blue inlay wax is commendable, and can be softened in the flame. Good results can be obtained, if handled care- fully. Making of die The impression in the seamless band is invested in plaster and when plaster is hard, filled with silver and tin amalgam, carefully packing it into all the grooves and corners. If there is a post in the inlay this should be withdrawn with the impres- sion. Cover the end of the post, extending out of the impression, with a thin film of wax so that it can be removed from the amal- gam die later. After the amalgam has hardened, the modelling compound should be softened in moderately warm Avater and removed. The die is now trimmed best with a sandpaper wheel on the lathe. In case we want to carve the wax on a model, trim the distal and mesial ends of the die cone-shaped, so as to be able to remove it from the model, then place it into the plaster impression taken for this purpose from the mouth. Make an articulated model from the metal die and bite. Carving inlay The wax pattern is now placed into the die. Sometimes it has to be slightly warmed first, but not enough to lose its form, nor press it out of shape. After it gets hard, carve it with special carving knives, reproducing all the cusps, grooves, fis- sures and sulci, which are best copied from a good selection of extracted teeth, or a good model taken from a mouth of perfect teeth. After carving the wax, Taggart recommends smoothing the surface by the aid of alcohol or chloroform. Place a sprue wire, which is to be of the size of a common pin (but a large one will do), into the greatest bulk of the 122 CROirNS AND BRIDGES wax, Eemove the wax from tlie model carefully, and with a very fine cameFs bair brush remove all fatty substances by painting the whole surface with alcohol; this makes it easier for the investment to stick. Place the sprue wire on the sprue, fixing it with wax if necessary. Investing Proceed as described in chapter on casting. Cast Cast as described in the chapter on casting. It is best to use ever}^ time new gold as it is seriously affected by every re- melting. B. BANDED CROWN ABUTMENTS 1. Base for Banded Abutments 1. soldered cap (Abutment II) See Crown VI. 2. burnished caps (Abutment III) See Crown VII. 3. SWAGED CAPS (Abutment IV) See Crown VIII. II. Supplies for Banded Abutments A. WITH FACING (Abutment IIa, IIIa, IVa) See Crown VIA, VIIA, VIIIA. B. WITH DETACHED POST CROWN (Abutment IIb, IIIb, IVb) See Crown VIB, VIIB, VIIIB. C. WITH GOSLEE TOOTH (Abutment lie, IIIc, IVc) See Crown VIC, VIIC, VIIIC. D. WITH STEELE TOOTH (Abutment IId, IIId, IVd See Crown VID, VIID, VIIID. I'lXI'J) BRIDGES 123 G. ALL METAL ABUTMENTS (Abutment V) 1. HALF GROWN WITH POST Preparing of tooth Iveiiiove pulp under rubber daiii b}' opening the to(jtli on the palatal side, near cutting edge, so as to get in straight line with the root canals, and (ill the a])ex of the root canal care- fully. Enlarge the canal and til an ii'idio-])latinnni |»ost into same. Fig. 119. Hall crown with post. Remove the post, reduce the tooth to clear the bite of the opposing teeth, have a 21-gauge space to allow for gold plate and reinforcement of the crown. Cut awa^^ the approximate contour of the tooth on the side where the dummy is to be attached; this may be mesially, dis- tally, or on both sides. Remove all contour on that surface of tooth to be covered. Making of die Take plaster impression of the prepared tooth Avithout the post. Remove the plaster impression, bank both sides of the im- pression of the tooth with moldine, and flow low fusing metal into it. Pull the metal from the impression, and file the neck of the metal tooth on the palatal and approximal side, to reproduce the shape of the root under gum margin, so as to allow the gold backing to extend slightly below the gum. Making of crown Swage a 24-karat 3()-gauge gold backing over the back of tooth. Trim and fit the swaged backing to tooth in the mouth. 124 CROM'NS JND BRIDGES Force the iridio-platinnm post through the backing into canal opening, allowing the post to extend a little through backing. Flow sticky wax over backing and post, remove carefully, invest and solder, or take a plaster impression. Kemove backing and post carefully from the tooth, place them into their place in the impression, and cast a model. Solder the post to the backing and flow solder, evenly, over the palatal surface, but not on the mesial and distal wings. This is to allow for the burnishing into place at the time of cementing. Be sure to use a light yellow cement for the setting of the lialf crowns with post, to bring out the natural color of the tooth. 2. STAPLE GROWN (Abutment VI) Preparing of tooth Grind the occluding portion of tooth so that a space equal to 24 gauge is left between the occluding tooth or teeth. With thin safeside carborundum disc cut enough contour from the mesial and distal surfaces of the tooth to allow a 30 gauge gold plate to pass between the adjoining tooth. Remove all contour from palatal side of the tooth. Then cut a horizontal groove for the staple. This groove should be started well toward the cutting edge 'of incis.ors and through the occlusal fissure in bicuspids. ( In most cases this groove is best started with a thin carborundum disc.) For mesial and distal grooves use a round bur (size S. S, White 1). The grooves can be enlarged with a fissure bur to 18 gauge. Note. — Extreme care must be taken to have mesial and dis- tal grooves parallel to each other and with the long axis of the tooth. Fitting staple Measure the length of mesial groove with 18-gauge iridio- platinnm wire. Mark the wire at point where mesial and horizontal grooves meet, and bend it at the point marked. Hold the wire into the horizontal groove with the bent end in the mesial groove and mark the wire, for the length of hori- zontal groove. FIXED BRIDGES 125 Bend at the mark. Measure with plain wire the length of distal j^roovc, and mark the length on the platinum wire. Cut the wire at that mark and file the ends sc^uar*'. By adjusting and bending, fit the staple accurately, and see that it fits firmly. Making of crowrn Place staple into position and take a plaster impression of the tooth. Remove the plaster impression and place the staple wire into the impression. Flow low fusing metal into it. Pull the metal from imj^ression and file the neck of the metal tooth to reproduce the shape of the root slightly under the gum margin. The staple is now in the metal die. Swage backing of 30-gauge 24-karat gold plate over the back of tooth (metal die). Have the gold backing cover the tooth, from cutting edge to below the gum line, and extend it mesially and distally be- yond staple wire. Fig. 120. Steps for making of staple crowns. 126 CROWNS AND BRIDGES Kemove the backing and leave it in nitric acid for a few minutes. Force or melt the staple ont of the die, and place it in the groove of the swaged backing. Catch it at one point with 22-karat solder, and fit the crown on tooth in the mouth, by pressing against the staple of crown to force it to place ; bur- nish the whole surface. Kemove and complete the soldering of the staple. Boil in sulphuric acid, trim and place it on the tooth, take wax bite and impression for the bridge. ( See steps, Figure 120.) Note. — When soldering dummies to a staple crown, flow the gold solder well over the backing, the palatal surface of the staple crown, except at the mesial and distal wings, which should remain soft so that they can be burnished. Use light yellow cement for the setting of staple crowns, and burnish the wings, when cementing, to get close adaption on mesial and distal parts. 3. OPEN-FACED CROWN, GLOVE FIT (Abutment VII) See Crown IX. 4. OPEN-FACED CROWN, OTHER METHOD (Abutment VIII) See Crown X. 5. TWO-PIECE ALL-METAL GROWN (Abutment IX) See Crown XIA-XIB (swaged and cast cusps). 6. SEAMLESS PRESSED CROWN (Abutment X) See Crown XII. 7. SEAMLESS SWAGED CROWN (Abutment XI) See Crown XIII. 8. CROWN WITH PORCELAIN FACING (Abutment XII) See Crown XIV. B. SUPPLIES FOR BRIDGEWORK There are different ways of supplying the lost teeth. The best supply is the one that has a porcelain chewing surface, but with a close bite, gold is advisable to give the desired strength. FIXED BRIDGES \21 1. CAST SUPPLIES fSupply I) Make articiilatcMl plastoi- models, Avitli abutiiieiits iji place, and press softened inlay wax between tliem. (Fi<;nre 121.) Occdude the articulator so as to i-ct ini]H-int of tlie occlnding Fig. 121. Model on articulator for cast supplies. cusp, the teeth occlnding opposite. Make also masticating mo- tions. When cold carve the wax as nearly like the cusps of natural teeth as occlusion will i)ermit. Slant the wax on the under side, so as to form a bevel toward center, or a Y-shape in cross section. Remove wax from the model, insert a sprue wire, invest and cast with 20-karat gold. (Figure 122.) Stone or file casting and wax it to the bridge abutments. Fig. 122. Supplies before and after casting. 128 CROWNS AND BRIDGES 2. FACINGS WITH DOUBLE BACKINGS (Supply II) Bevel back of cutting edge of facing. Cut out 31-gauge 24-karat backing to extend from the ridge lap and bej^oncl the cutting edge. Anneal, punch holes for pins and burnish it on the facing. Then insert in modelling com- pound and swage, but do not have backing bent over cutting edge. Cut a 26-gauge 18-karat backing to extend from below pins to over cutting edge. Punch holes. Burnish and swage this in place over the first backing. Do not swage second 24-gauge Fig. 123. Facings with single and double backings. backing on thin or narrow teeth, as the facing is liable to crack. Bend such a backing approximateh- to fit, and till the space between the two backings with solder. Remove backings and unite them by flowing solder between them so that this will show at all edges. (Figure 63.) Boil in 20% sulphuric acid. Replace the backings on the facing and burnish it around the pins with a hollow burnisher. Do not cut or split the pins. File to an approximate finish; then wax the facings to the abutments. Remove the model from the articulator, cut surplus plaster off and invest in a good investment, so that nothing is exposed except the backing and metal of the abutments. A small in- vestment ring is often very advantageous to hold the case to- gther. Cut the investment to get free opening to the parts to be soldered. Heat slowly over the flame and solder. 3. FACINGS WITH SWAGED CUSPS (Supply III) Grind suitable facing to fit the gum and the bite, leaving a space of 24 gauge between edge and occluding teeth. Bevel the cutting edge of facing on the back side. FIXED BRIDGES 129 Swage 31-gauge pure gold backing to the facing, allowing it to extend tjV of an inch over tlie cutting edge. Wax the backing to the pins and the whole on the articulated model, using sticky wax. Build cusps with pink base plate, wax and occliule to get tlie imprint of the opposite teeth, then carve the occlusial sur- face as nearly as jjossible to natural shape. Chill the wax cusps and take an impression of them in moldine. Flow a Melotte's metal die. Make a counter die if neces- sary. Swage the cusps of 22- or 24-karat, 31-gauge gold plate, place gold plate over the die, using a small swager if possible. Drop in nitric acid for a few minutes to remove Melotte's metal. Trim the gold cusps to the proper size. Place them on the wax cusps on the model and settle them to place Avith a hot spatula, trying the occluding bite. ( P'igure 12J:A.j A B Fig. 124. Facings with swaged cusps. A, normal ; B, for close bite. When the case is all set up, add investment to the model to hold the cusps and backed facing in position. Invest in a metal ring. Boil the wax out. Dry. Heat np and solder, filling the space between palatal edge of cusps and cervical edge of the backings first, then connect the individual dummies, and the dummies to the abutments. Fill all level with solder. Let cool slowly, cover the case to prevent draft from touch- ing it. File tlie cutting edge of the metal in a continuous line with or at an obtuse angle to the labial surface of the facing, so that the occluding teeth will not strike the facing. Note.— In very close bites, use double backing, attaching cusps to a part of the backing bevond the cuttino- ed^e (Fio- ure 124B.) ' ^^ = • v ^ 130 CROWNS AND BRIDGES 4. DETACHED POST CROWNS IN BOX (Supply IV) Grind the porcelain crown, which can be hand-carved, or a stock crown to occlude and fit the gum at the labial or buccal side. Leave space enough for the thickness of the box and its reinforcement. Swage a box and fit a post as described in crown VIB or VIC. ( Figure 139A and D. ) To add strength to the box and post, solder a piece of 18- or 20-karat 28-gauge gold plate over the base of the box. (Fig- ure 139B.) Wax the boxes with teeth to the abutments and remove the teeth before investing. Paint the inside of the boxes with anti-flux, cut the model from the articulator, and extend the investment to fill the boxes. Solder with 18- or 20-karat solder to get about the natural shape of the teeth, 5. STEELE FACINGS (Supply IV) Steele facings may be used to advantage as supplies instead of pin facings, in bridgework. Grind Steele facing to fit the gum and bite. Do not bevel the tip of facing as is done with pin facings. (Figure 125.) Fig. 125. Bridge with supplies of anterior Steele teeth. Fit a Steele backing to the ground facing, trim off over- hanging edges of the backing, except at the incising edge, where the backing should be left longer than the facing. (Figure 129. ) Wax, invest and solder. When the bridge is finished, do not file the backing flat at the end of the facing, but use the flle in a line contiuous with the labial bevel of the facing. Do not cement the Steele facings to the backings until the bridge has been tried in the mouth and is found to be perfect. FIXED BRIDGES 13; Cement tliem to tlie hriil/^e before cementinji' tlie latter into the mouth, using' a right color cement. Note. — Be sure in all cases to wash the bridge well; h.ave no acid on bridge backings or tooth boxes, as otherwise a ce- mented tooth (the cement) will be affected by same and drop off. Fig. 126. Steps for making of Steele anteriors crown. 6. STEELE POSTERIORS (Supply VI) In using Steele posteriors as supplies in bridgework, first grind the tooth to fit gum and bite. Place Steele backing in place on the tooth. Burnish or swage a piece of 35-gauge 24-karat gold over the back part of the tooth not covered by the Steele backings, and allow it to extend slightly under the edge and sides (Figure 132 of the lat- FiG. 127. Steele Anti-flux. Indispensable in crown and bridge work. 132 CROPFNS AND BRIDGES ter). Wax the 24-karat gold extension to the Steele backing with sticky wax and remove it from the tooth. Paint the in- side of backing and extension with Steele anti-finx. (Figures 127 and 128.) Invest and solder them together, or hold in ■fSS Fig. 128. Painting of backing with Steele Anti-flux. A B Fig. 129. (Oblique line) right and (arrow point) wrong way of filing backings. Fig. 130. Filing to remove obstructions. ^r-/ ^ / Fig. 131. Bridges with Steele posteriors. FIXED BRIDGES 133 place and solder in open flame. (Fij^iire i:i2.) Place backinj^ and extension back on the tooth, and burnish it to accurate fit. To make a box, use a common leather or ticket punch and punch hole in a 24-karat gold plate, solder plate to Ijackino- (Fioi,r(^ 134). Swage to Steele posterior or as per Figure 139D. Fig. 132. Soldering extension to backing. Fig. 133. Fitting to tootli. Fig. 134. Steps for making of box of Steele posterior. Fig. 135. Above bridge with short teeth, and short gold crown abutments ; this has no wash spaces, and its weakest point is where the Steele posterior molar joins the gold crown. 134 CROWNS AND BRIDGES Place backed tooth in position on the model in its proper relation to the abutments. Wax backings to the abutments. Kemove teeth from backings. Paint inside of backings with Steele anti-flux. Invest and solder the dummies and abutments together. Note. — To obtain strength and Avash space in close bite cases when the Steele posterior fits close to the gum margin and the abutment, leave a V-shaped space between Steele tooth and gum margin. (Figure 136.) Burnish or swage the Steele Fig. 136. Steele posterior molar with slice cut from the distal side ; this will overcome the weak place next to its abutment, as shown in case above. backing over the bevelled surface and proceed as above. Base metal posts and backings as these will not stand the soldering and acid. @iqp Fig. 137. Notice the wash space and freedom of the festoon next to crown abut- ments and dummies. This is very important and should be provided for in all fixed bridges. 7. GOSLEE TOOTH (Supply YU) Goslee teeth can be used as dummies with or without saddle, as the case may call for. Grind Goslee tooth to fit the bite and the gum, leaving suffi- cient space between gum and Goslee tooth for thickness of box, as described for crown VIC. To swage a box for a Goslee tooth, invest the to^th in mod- elling compound as shown by centre (Figure 139D.) Swage 35-gauge pure gold box. Solder a post to the box and reinforce same. (Figure 189B.) 39 CHl .Jk^JUk._'^_ ri I . liJ 49 i^l ^mmQry Fig. 138. Anterior and posterior Goslee teeth. H Fig. 139. Steps to show making of boxes for Goslee teeth, or other porcelain crown. 136 CROWNS AND BRIDGES If the box with post is soldered to a cap or a saddle (Figure 139C), it will give sufficient strength. In other cases one cannot depend on the reinforcement of the boxes with solder only. In many cases the solder is drawn or polished from the box and weakens, as shown by arrows A and B, Figure 139B. Fig. 140. Anterior Goslee bridge. Fig. 141. Posterior Goslee bridge. To prevent the post from being pulled out of the box, and to prevent the solder from being drawn away from the high point (A), bend and solder a strip of 18- or 20-lvarat gold plate 26- or 28-gauge to the box, as shown in Figure 139B. This can be done in the open flame or in an investment. It should be done before soldering the box to the abutment. 8. EVSLIN INTERCHANGEABLE TEETH (SUPPLY VIII) This type of porcelain supplies comes with ready-made, adaptable backings. Perfect boxing can be obtained (Figure 142) by swaging the backings to the Evslin tooth. Fig. 142. Evslin interchangeable teeth for crown and bridge work. FIX HI) BRIDCES 137 G. ASSEMBLING BRIDGES Bridge I I. SANITARY BRIDGES a. Sanitary bridges with gold chewing surfaces After tlie supply is cast, it is waxed to the abutments. (Figures 121-122.) Fill the space between the snp]»lv and unui ^\\\\\ investment. (Figure 143.) Fig. 143. Soldering of casting to all metal abutments. Eemove the model from the articulator, trim it to small size and heat it slowly. Solder from the occlusal surface with 18- or 20-karat solder, stone and polish. Fig. 144. Top view of sanitary bridge. Fig. 145. Sanitary bridge witli gold casting. 138 CROWNS AND BRIDGES b. Sanitary bridges with porcelain chewing surfaces. _> Bridge IV. If there is sufficient space between the teeth of the opposite jaw and the gum, use detached post crowns, or other porcelain boxed teeth, to get a porcelain chewing surface, which masti- cate better and give a better appearance. This is especially important for orators or singers. These porcelain crowns should be trimmed down sufficiently, however, so as not to take up too much space. The gold underneath is again V-shaped, so that it can be easly kept clean from both sides. Make a model witli the abutments and grind the detached post crowns or diatoric teeth to get a good occlusion. Then shorten them at the lower part, but not enough to weaken tln^ crown. Proceed as described for supply IV. After the bridge is invested and heated up, floAv 18- or 20- karat solder over the boxes. Sometimes, especially if the bridge is long, it needs to be reinforced with a strip of 18- or 20- karat plate gold placed over the boxes. The boxes could also be waxed together, cast and then soldered to the abutments. Stone grind and polish. (Figure 146.) 2. SELF CLEANING BRIDGES (Bridge III) Fit supplies and wax them in the correct position on the articulated model. Make a plaster core around supplies and abutments. Boil out the wax, study and mark the teeth for length of backings. Remove supplies from the core and fit the backings or boxes. Backings must reach to the gum line. Test this by placing the supplies with backings on the model with cores. (Figure 65.) Boxes must clear the gum line sufficiently to allow for their reinforcement, Avhich is not less than 24 gauge. Place cores on the models and supplies into same, wax the supplies together (not more than four in a section, use a wire in the wax for stiffener. ( Figure 208. ) Remove this waxed section, from the core, invest and solder (or cast). (Figure 209.) Before. After. Fig. 146. Sanitary bridge with porcelain chewing surface. 140 CROWDS AND BRIDGES Fig. 147. Self-cleansing bridge showing wash spaces. Boil the soldered section and replace it in tlie core on the model. Wax soldered dummies or sections to the abutments. Remove the cores, invest the whole bridoje on the model in plaster and Portland cement, or other investment. Solder the supplies to the abutments as shown in Figure 65. Cool, boil in acid, stone and polish. 3. SADDLE BRIDGES (Bridge IV) Continuous saddle Outline the area on the model to be covered by the saddle. (Figure 148.) Swage or cast the saddle. Swaged saddles can be made of gold, but are better of platinum 32-gauge. The latter are the cleanest. Cast saddles are made hj pressing thin casting wax over the model, and trimming it to the outline. Put sprue into the center, and paint with inlay investment. After this has hardened, remove it from the model, invest and cast. Thin platinum saddles can be stiffened by gold casting to same. Place the saddle on the model. Follow steps as for bridge II. Backings and boxes may rest on the saddle. (Figure 150.) Place supplies on the model with cores. (Figure 149.) Wax supplies to the saddle. Remove core from the supplies and model. Remove teeth from the boxes, and paint the inside of the boxes with Steele anti-flux. Remove saddle with waxed boxes from model. Cast with 20-karat gold. Invest and solder. (Figure 150.) Boil in acid, and rough stone this section. Fig. 148. Saddle bridge. Teeth in core before boxing. Fig. 149. Saddle bridge. Teeth boxed. Fig. 150. Saddle and boxes invested ready for solder; investment opens from front and back. 142 CROWNS AND BRIDGES Fig. 151. Saddle bridge, before and after cementing of supplies. Place back ou to model, and wax it to the abutments. Invest the whole bridge on the model, in a ring with plaster and Portland cement. Boil the Avax out, solder, boil in sulphuric acid, stone and polish. Care should be taken to allow sufficient space between the abutments and the saddle for the faestum of the gum. Porcelain saddles If there is a great deal of absorption of tissue, saddle bridges sometimes necessitate the showing of gold to avoid too long teeth. This can be overcome by the use of gum blocks, either Fig. 152 shows a banded porcelain molar crown, and bicuspid dummy. The slotted porcelain crown and dummy were carved in one piece and cemented to metal base on molar roots. FIXED BRIDGES 143 baked and soldered to the saddle, or still better by entire gum blocks with i)orcelain saddles. These are attached to hoth abutments by bars extending from bi'idge abutments and being Fig. 153. Hand-carved porcelain blocks with porcelain saddles. cemented into the block. They are very clean and give excel- lent effect. (Figures 152 and 153.) Follow general instruc- tion as for making single hand-carved crown. Individual saddles When planning to use a saddle, make a thorough examina- tion of the ridge which is to be covered by the same. It is almost always necessary to carve the plaster model to allow the saddle to set firmly on to the ridge, without having an open- ing at any place except next to the abutments. Individual saddles are most practical for dummies, which are carried by abutments at each end, such as from cuspid to molar bridge, or bicuspid to molar bridge. These individual saddles permit wash spaces between each crown and dummy, which is of great advantage in the cleaning, also to the feeling to the tongue, as it is more natural, is the nearest restoration to nature of the missing teeth. (Figure 139C.) Continuous saddles are more practical for extension bridges, such as shown in Figures 151 and 210. These continuous sad- 144 CROWNS AND BRIDGES dies are also used to cover a larger surface, but this all depends on the strength of the abutments, the bite and the ridge. In all cases the platinum saddle is preferable to the gold, be it for a cast or a soldered bridge. Platinum or porcelain saddles are less irritating, and have proven cleaner than gold saddles, in all practical cases. 4. EXTENSION BRIDGES (Bridge VI) Fixed extension bridges are always saddle bridges. The force of mastication should be taken up b}^ the alveolar ridge, to a great extent, and not so much by the abutments. The further away we can remove this pressure from the abutments the longer will these last. Fig. 154. Extension bridge from front and back; note space for festoon, to allow for gum between crown and saddle. The construction of these bridges is similar to the foregoing ones, being usually saddle bridges, with abutments only on one side. (Figures 154 and 151.) { Bridge VII ) Interlocking bridges Whenever it is impossible to line up or bring into parallel lines the teeth, and roots, which are used for bridge abut- ments, one can use an interlocking device, by which the diffi- culty of fixed bridges is overcome. Various devices such as the Morgan attachment, the Roach attachment, the split-bar attachment, and many others, are offered for sale by the dental depots, and all of them have their place in this line of work. See description of these appliances. (Figures 184-191.) If the dentist does not care to use any of these appliances, but prefers to make his own, he can easily accomplish this in the following manner. Make a dove-tail, or tube attachment, either by bending double plates and reinforcing same with solder, or by tile casting process. Care must be taken in all cases to set these attachments at a right angle or in parallel line with the fixed abutment. (Figures 17 and 18.) IX. REMOVABLE BRIDGES Removable bridges are the next step to the fixed bridges for the replacement of lost teeth. If the abutments are not strong enough to support the new teeth, for fixed bridges, then use the alveolar process to support the appliances. These bridges, if well constructed, and in the right place, are very useful, al- though they are not as ideal as fixed bridges; nevertheless, they are far superior to a plate. Dr. Pieso's, Dr. Ash's, and other removable bridge systems have been described so often in the past, that I will content myself with the later and less known systems, such as the Gilmore, Roach, and Morgan types. A. REMOVABLE BRIDGES WITH GILMORE ATTACHMENT GENERAL DESCRIPTION OF TECHNIQUE PREPARING GAPS AND POST FOR GILMORE ATTACHMENTS The Gilmore attachment is a V-shaped clasp ( Figure 1 83 ) . This clasp is fastened to the removable bridge saddle (or plate j , and is engaged to a 14-gauge platinized gold wire, which is sold- ered to a crown, cap or inlay. This wire can be extended from a single abutment, or the wire can be soldered to two or more abutments, and as many attachments used as to the size of the bridge. Great care must be taken in the preparation of such roots, and teeth to be used, if they are to he connected hy the gold icire; the posts in the root canals and the gold croAvns or inlays must be parallel to one another. (See Figure 159.) The Ijridge meter is of great value in tliis work. (Figure 201.) With a single extension no such care is necessary. It is advisable to start trith a simple case, such as a remov- able bridge between a cuspid and molar, or bicuspid and molar 146 CROWNS AND BRIDGES witli crowns. After making the crowns in the usual manner, take a wax bite and a plaster impression of the crowns in place and of the tooth space. Before placing the crowns back into the plaster impression, line the inside of the crowns with a thin film of wax, so that when the model is made, the crowns can be warmed and pulled off. Make an articulated model, warm the crowns and pull them from the model, boil off the wax and place them back on to the model. Fit a 14-gauge platinum wire from crown to crown, bending the end of the wire upAvard. ( Figure 1 83, B and C. ) The wire should lay on top of the ridge, if possible. Wax the wire to the crowns, remove all from the model, in- vest and solder wire to the crowns. Place the gold frame back onto the plaster model. Now proceed with making a cast or SAvaged saddle. Another simple case to start with, would be to solder an ex- tension wire to the lower bicuspid crowns. ( See cases Figures 179, 182, 183B and C.) Solder the gold wire (14-gauge) to the crow^ns, take bite and impression in plaster. Make a partial lower gold bar denture, gold or rubber sad- dles with a Gilmore attachment at each end. In setting the crowns with the wire extension, it is best to place the crowns with the wire in the attachment on the denture and then cement ilie croiois icith the denture to place. In using roots for abutments it is well to Ituild the root caps to the level of the gum, as otherwise the gums will fold over the root caps, and it is hard to care for them by the patient and dentist. The wire can extend to one side of a root cap, but I have had my best results by soldering the wire across the root cap, ex- tending mesially and distally with an attachment at each end. (Figures 170, 171.) For the construction of large frames and to finish the bridge such as shown in Figures 173, 174, loith one plaster impression (with the abutments in place) do as follows: REMOVABLE BRIDGES 147 FITTING PLATINIZED GOLD WIRE TO THE ABUTMENTS FOR GILMORE ATTACHMENT Place abutments in position on roots or teeth. Take Avax l)ite and ])laster impression ;is for n rubber plate. (Figure 155.) Fig. 155. Plaster impression of four abutments. Before placing the abutments in the f)laster impression, flow a thin fllm of wax over the posts and inside of the bands and crowns, so that they can be removed later from the plaster model. Make a plaster model. (Figure 156.) Mount model, and bite on an anatomical articulator. 148 CROWNS AND BRIDGES Kemove the wax bite. Shellac or varnish plaster model, and take a plaster impression of the model with the abutments in place. This is for a large case only. Note.— Care must be taken to fill with wax all undercuts on the model, so as not to break the model when removing the plaster impression from it. Fig. 156. Plaster model with four abutments. Eemove the plaster impression; heat and remove the abut- ments from model (Figure 157) and place the abutments in their positions, in the netv plaster impression, making them se- cure by flowing a little sticky wax around their edges. Make this, the second model, of plaster and Portland cement or other good investment. To this model fit a round 11-ga.uge 18-karat platinized gold wire over the center of the root-abutment, and over the ridge of the gum, so that it barely touches the model between the abut- ments. If the posterior abutment is a crown, bend the wire so that it will fit upright on the center of its mesial surface. (Fig- ures 185B and C.) REM O I 'A BL li nRJI) C; ES 149 Fasten tlie gold wire to the model with binding wire, and solder the wire to tlie abutments with 18-karat solder. Boil the framework in aeid and place it on the first original plaster model. (Figure 157.) Figure 158 sliows finished Fig. 157. Abutments removed from model to solder wire frame. Fig. 158. Finished frame in position. 150 CROfVNS AND BRIDGES frame. In small cases the gold wire could be fastened to the abutments of the original model with sticky wax ; taken off the model, invested, and soldered. Fig. 159. Finished frame for another case. Making of bridge proper Place a plain opened Gilmore attachment (Figure 183, No. 5) {i.e., without any extension) over the wire where desired, and make a swaged or cast saddle to cover the framework, the attachment and as much of the gum ridge as you wish to cover. (Figure 183H.) Making of cast saddles Place a jDlain open dummy attachment over the wire (Fig- ure 183, No. 5) ; slightly oil or vaseline all the territory to be covered b}^ the model wax. On removing the wax it will be found to bear an imprint of the attachment and bar, which features are reproduced in the casting, indicating the position the attachment should occupy in the completed case. The ob- ject in using ojieii attachments is to prevent tlie metal from being in absolute contact with the free wings of the attach- ment, after the gold attachment has been soldered in position, and also to create a channel on each side of the clasp, so that it can be adjusted for tension. In partial, and full cases as well, I would like to point out the importance of placing the clasps or attachments "straight" on the wire, for if the attachment is tilted to one side, the plate or saddle to which it is fastened will spring up from the wire during mastication. When the extension wires run parallel to one another (Figure 182), the denture will slide back, and leave a space to the adjoining teeth. This is overcome by soldering a knob at the end of each extension wire, and set the attachment close to this knob. Fig. 160. Frame and Gilmore Attachments in position on flasked model. Before packing with rubber, tinfoil the whole case, open the attachments, and cement them over the tinfoil to place. Fig. 161. Other half of flask. 152 CROWNS AND BRIDGES This knob can be produced by heating the end of the gold wire until it melts, and forms a thickened round end. A gold color soldered to the end of the wire will also answer the same purpose. Whenever the extension wires are spread, as in Figure 179, no trouble of sliding of the denture will be experienced. For one side dentures (see Figure 180), I have found this loop extension with two attachments very practical. Fig. 162. A full lower Gilmore denture. Case before treatment. Cut a slot through the saddle over the center of the position of the attachments. Fit attachment No. 6, Figure 183 (with the pin through the slot in the saddle) . Open the attachment slightly to allow it to slip on and off the wire easily, then paint the sides of the attachments with Steele anti-flux. Place it in position in the saddle, and wax the extension to its outer surface with sticky Avax. Invest the inside of the saddle and the clasps. Remove the sticky wax and solder the clasp extensions to the saddle with 18-karat solder from the occlusal side. Note. — Great care must be taken to have the attachment in a vertical axis. Gilmore attachments must all be parallel Fig. 163. A full lower Gilmore denture after treatment. Finished frame on model. Fig. 164. Full upper Gilmore denture. Frame finished to show abutments and gold wire on model. 154 CROWNS AND BRIDGES to each other, as a slight tilting of the attachments will make it very difficult to seat and remove the saddle. Place the swaged or cast saddle with attachments on the articulated model. Grind all supplies into position and wax them to the saddle. Follow steps as for ordinary saddle bridges. (See bridge IV.) Place supplies into the core on the model. Backings and boxes may rest on saddle or plate. Wax supplies to the saddle. Kemove saddle with the supplies from the model. Fig. 165. Another full lower Gilmore case. Finished frame on model. Paint the Gilmore clasps in back of saddle with Steele's an- ti-flux. Invest the Avhole into a ring or band. Boil the wax out, heat carefully and solder. Boil in acid, stone and polish. Now close the open attach- ment to fit the wire soldered to the abutments. This is done by placing a piece of a wire inside of the clasp and applying pres- sure with flat-nose pliers. Splendid results have been obtained with this attachment in small and large cases alike. Roots slanted If the roots are slanted, one is not able to use a fixed frame- work, and then one has to devise variations as required for spe- REMOr/JBLE BRIDGES 155 cial cases. Hncli a ease is sliown in Fionre 220. To tlie cus- pid caps is soldered a loop allowing the caps and posts to swing in position of the slanting cuspid roots; the other four caps are soldered to the gold wire. Fig. 166. Full upper Gilniore denture. Case before treatment. Fig. 167. Same case with finished frame in position. 156 CROWNS AND BRIDGES Material These bridges can be made in various ways, as for tempo- rary bridges, by using rubber. Also, if the patient cannot af- ford gold, other material, such as rubber or combinations of gold saddle with rubber attachments, can be used. The differ- ent combinations are : — 1. Eubber. 2. Gold saddle with hand-carved teeth, detached post crowns, Goslee or Steele tooth and similar teeth. Fig. 168. A plaster model of the back of finished denture. 3. Platinum saddle with crowns, Goslee or Steele teeth, hand-carved teeth or detached post crowns, or others. 4. Platinum saddle with gum blocks. 5. Platinum saddle with teeth soldered on, or continuous gum baked on. Different kinds of bridges with Gilmore attachments as shown (Figures 158 to 182.") 1. FULL BRIDGES (Removable Bridge I) Very frequently there are only a few roots or teeth left in the mouth, and as they would be too weak to serve as abutments REAW yABLE BRID GES 157 for a fixed bridge, they could be utilized, when in healthy con- dition, for the retaining of a removable bridge. The principle of the removable bridge is to bring most of the stress of masti- cation on the alveolar process and gum, so as to prevent the attachments from being forced out of place by the force of the bite, tlie tongue, cluH'ks, lips, etc. It is, of course, of greatest importance to set the teeth up for anatomical articulation, so that mastication does not strain the attachments, on acc<)nn' of faulty occlusion. Case: Figure 169. This patient, 7Z years of age, had but one good upper cus- pid tooth, but a complete lower set of her own teeth. She had a very flat palate, and had never worn a plate of any kind. Gilmore attachment was made as follows: The upper cuspid was cut off, and a swaged platinum cap with a platinum post was fitted to the root. To this cap and post a 14-gauge platinum gold wire was soldered; this wire was pointed toward the center of the palate. A Gilmore attachment was fitted almost to the end of the wire, and over this a thin 20-karat gold plate of 36 gauge was swaged, also having a gold mesh wire soldered on the surface. (This is known as a Perfection gold plate.) To this the clasp was soldered, and a full upper set of 14 teeth were vulcanized to the plate. The patient could wear the plate with comfort from the first day, and as yet the root shows no sign of loosening. Tf later the root should give way, the patient no doubt would then find no difficulty in wearing a plate that was dependent wholly upon suction. 158 CROWNS AND BRIDGES One can ntilize even one strong single root for this purpose. (Figures 169 and 171.) Two or more are of course of greater advantage ( Figures 170, 165, 163, etc. ) , and insure longer ser- vice. It is advisable to make a full plate with the attachment to any weak supports, as narroAV ridge, or skeleton plates, bring too much pressure on the abutments. (This refers to full cases.) The illustrations show various practical cases that have proven very satisfactory. Fig. 170. Full lower with two roots and two Gilmore attachments. 2. PARTIAL BRIDGES (Removable Bridge II) For partial removable bridges, gold crowns, banded porce- lain crowns, and inlays are of the most frequent abutments used. These small bridges can be made by different methods, and some of these methods are here described. 3. PARTIAL BRIDGES WITH VAULT BAR (Removable Bridge III) If a number of teeth on both sides of the mouth are to be supplied, it is of advantage to connect them with a vault bar to prevent lateral stress. This bar is closely adapted to the palate. Take a strip of pure gold 30 gauge and burnish it on the model, from one saddle to the other. This is then rein- forced with an oval bar of platinized gold, and soldered to the strip of pure gold and also to the saddles of the two lateral parts of the bridge. The vault bar should be so constructed Fig. 171. Full lower with one root using two Gilmore attachments. This was a case one could not expect too much from as far as the lasting of this one root was concerned, but time has proved it to be satisfactory beyond all ex- pectations. It helped the patient, an old lady, to get accustomed to the plate. 160 CROWNS AND BRIDGES that it does not interfere with the movements of the tongue in speaking. As a rule, it should be as far back as possible. Cast bars of clasping gold are good for such cases. 4. PARTIAL BRIDGE WITH LINGUAL BAR (Removable Bridge IV) The above is also true for removable bridges for the man- dible. The two halves are connected with a bar extending along the lingual part of the gum of the front teeth. Fig. 172. Anterior fixed and posterior removable bridge with Gilmore attach- ments. A, shows the roots before treatment. B, anterior bridge with wire extensions in place. 5. EXTENSION BRIDGES FOR ONE SIDE (Removable Bridge V) If teeth are missing on one side of the jaw only, either in the maxilla or mandible, we can use an extension bridge. The Gilmore wire is only connected on one side to the abutments, and extends out over the gum. This wire can also be bent in a loop, so as to give attachments for two clasps laterally. This prevents motion. (Figures 180 and 181.) i^^^_. Fig. 173. Partial removable bridges with three Gilmore clasps used in this case, one between cuspid and central, and one between the cuspids and molars on each side. A swaged saddle of platinum with hand-carved teeth soldered to it. B Fig. 174. Removable partial bridge. In this case the lost teeth were restored with a removable bridge. Gilmore attachment wire was soldered on the right upper bicuspid abutment and both cuspid roots, and left upper molar. Ten teeth, some with porcelain gum, were soldered to a swaged platinum plate, having three Gilmore attachments, one between the cuspid root caps and two between cuspid and molar on left side. Fig. 17S. Partial lower removable gold denture held with one Gilmore attach- ment to second bicuspid gold crown. Fig. 176. Removable bridge with vault bar. In this case the anchorage v/as obtained by crowns to the lateral and molar of the left side and by gold inlays with posts on two molars of the right side (Figure A). Gold saddles with vault wire and hand-carved teeth with porcelain gum were used. Three attachments, one on the right side, and two on the left side, held the bridge securely. Fig. 177. Removable bridge held by three Gilmore attachments. Fig. 178. Partial removable bridge witb vault I)ar, two Gilmore attacbments. Fig. 179. Partial removable bridge v^'ith lingual bar and two Gilmore attachments. Extension wires are soldered to bicuspid, banded crowns with Steele posterior supplies. The bridge is made in gold with hand-carved ?um blocks. ^H "^^^H l^^l ^B ^B^T^ -^ ^^^^^^^^H ^ ^^^^^^^1 H k;. ^^^^1 r ,^ ~^r^^ •""^^^H ^H '% '".r • ' -SS ^ ^^ /^i^^^^^^^l ^^M ^^ Fig. 180. Removable extension bridge for one side. Case showing a removable extension saddle bridge. A loop was soldered to an all-metal bicuspid crown, which was connected to an inlay with post in the cuspid. Two Gilmore attach- ments were placed one on each side of the looped wire, and over this a cast gold saddle was made, and the teeth were mounted to the saddle, as shown. _ A double attachment on a looped wire has a great advantage over a single wire, as the looped wire prevents the backward sliding of the saddle, gives more firmness to the bridge, and most of all it affords great strength where it is needed, next to the crown. Fig. 181. Top view of finished case No. 180. Fig. 182. When extension wires run parallel, as in this case, then the denture with the Gilmore attachments is liable to slide back. This should be taken in con- sideration when soldering the wires to the crowns, soldering a collar or knob to the end of the wire, and placing the attachments close to same, will over- come all back sliding of the denture. BUD No. 3 No. 4 No. 5 No. 6 Fig. 183. Different styles of Gilmore Adjustable Attachments. No. 3, No. 4, No. 5 and No. 6 are made of a special clasp gold. B C shows 14-gauge clasp gold wire soldered to gold crown. H shows No. 6 attachment soldered to saddle bridge. No. 3 and No. 4 are also made in special white metal and are intended for rubber work only and are sold as style No. 1 and No. 2. 168 CROJVNS AND BRIDGES B. REMOVABLE BRIDGES WITH ROACH ATTACHMENTS Removable Bridge VI The Roach attachments are constructed on the ball and socket principle, which eliminates leverage and obviates par- alleling, thus making its use very simple and efficient. 1. FITTING THE ATTACHMENTS TO THE ABUTMENT Fitting to gold crowns Make the crown and adjust it in the mouth ; mark the loca- tion for the ball about sV of an inch from the gum lingually, so that the attachments will line up with the lingual surface of the teeth; remove the crown from the mouth, drill a hole of the size of the stem on the ball at the point marked; cut the stem short so that it will not project inside of the crown, and solder Fig. 184. Roach attachments for removable bridges. it to place. The stem also may be cut off to the shoulder and the ball soldered to the crown without drilling a hole. (Fig- ure 184.) REMOVABLE BRIDGES 169 In some cases it is advantageous to take an impression of tlie crown in position and locate the attachment on the crown after the model is cast. Fitting to banded porcelain crowns Construct caps, adjust tliem in the mouth and mark the location for the ball, so that it may be waxed to place, invested and soldered simultaneously with the facing. Fitting to inlays After a wax pattern is secured, warm the ball and imbed the stem into the wax, try it again into the cavity to verify the fit of wax and the proper location of ball, invest and cast. The melted gold will unite with the stem of the ball and will need no soldering. The inlay may also be completed, the stem cut off, and the ball soldered to the inlay. 2. TAKING IMPRESSION FOR BRIDGE The abutment with the ball attached should now be placed in the mouth, take an impression, and form model, making sure that the abutment is securely held in place. 3. ASSEMBLING OF THE BRIDGE WITH ROACH ATTACHMENT Construct the saddle bridge in usual manner, placing the tube over the ball. The tubes are soldered to the bridge. One side of the tube should be left uncovered for the pur- pose of tightening. Tighten attachment by compressing tube with pliers, plac- ing an end of a match or piece of wire in the tube to prevent closing it too much. Note. — Open tubes slightly to facilitate removal during con- struction. G. REMOVABLE BRIDGE WITH MORGAN ATTACHMENT Removable Bridge VII of anchoring bridges ii- riginator claims that li€ tachment out thoroughly in hundreds of cases. Another means of anchoring bridges is Avith the Morgan attachment. The originator claims that he has tried this at- 170 CROWNS AND BRIDGES Making of the abutments All the different abutments suitable for fixed bridges can be used. The attachment consists of a two-winged curved piece (Figure 185A), into which fits a two-armed anchor (Figure 185B). The curved piece is called a keeper, and is to be sold- A B Fig. 185. Morgan attachments for removable bridge. ered to the gold crown abutment, banded crown or inlay abut- ment. The other piece is called the anchor, aiid its head is curved to fit into the keeper Avith a cap soldered on the top, the shank passes out between the wings of the keeper, and furnishes anchorage in the gold, or other material of Avhich the denture is made. The abutments are made in the usual manner: place them in the mouth, take impression and bite, and make articulated model. If you wish to avoid taking a second impression and making a second cast, flow a thin coating of wax inside the crown, before pouring the plaster cast, then by heating the crowns sufficiently to melt the wax, these can be slipped off and on at will, and the one impression and cast will do the entire work. To adjust a keeper to each of the abutments, and to have both perfectly parallel to each other, tlie originator constructed a jig. (Figure 186. Fig. 186. Jig for Morgan attachments. REMO FABLE BRIDGES Fasten the jilastcr modd t(» tli<* luisc of tlic ji^ \)y means ol' the thumbscrews. Slip tlie kee])(M-s ovcj- llic forks of the jij;, Ix'iiij;- careful that tliey are put on evenly, as can be told l)y sightinj* past the edjie of both to see if the edges are in line witli each other. Loosen the tlnmibscrew on tlie nprijiht bar, and lower the keeper to the ])]ace beside the abiitiiieiits. dsi Fig. 187. Morgan attachments soldered to all-metal crowns. Wax them in place with sticky wax and when cold raise the guide forks out of the keepers. Loosen the thumljscrews and remove the model. Now remove the crowns from the cast, and wax them so that no plaster can come betAveen the keeper and the crown. Invest with that end of the croAvn upwards, which makes it most convenient for soldering. Make sure that the investment holds the parts in place, and that the curved slot in the keeper is thoroughly filled with investment. Cut the investment away Fig. 188. Morgan attachments used on various crowns. to give free access to soldering, boil the wax out and solder. Should the keeper stand away from the crown at one end, fill the space with gold-foil, so as to assure a strong joint when you solder. 172 CROWNS AND BRIDGES After having the keeper soldered to the abutments, fit them in the mouth, and take impression and bite for a new articu- lated model; but if you have saved your first cast by using a wax coating in the abutments, replace the abutments to the plaster model. Making of the supply As described for Gilmore bridges, one can use different ma- terials to supply the lost teeth : rubber facings, detached post croAvns, Steele teeth, Goslee teeth, and others. Fig. 189. Finished case of Figure 187. Slip the anchor over the keepers, slipping the metal loop which comes with the attachment over the anchor's sliank. Bend the latter down so as to keep it as much out of the way as Fig. 190. Saddle with single Morgan attachment. possible, when you are setting up the teeth. The loop is fur- nished with the attachments, and allows for stronger connec- tion of the anchor with the supplies. REMOVABLE BRIDGES 173 AVlien all the supplies are waxed up, solder the bridge in ordinary manner, makinii' snre to .uet a j;ood junction Ix^wcen the anchor-loop and tlie gold of the bridge. In case of a saddb' Fig. 191. Lower denture with Morgan attachments. bridge, the anchor and loop can also be soldered to the saddle first. The illustrations show some practical cases. (Figures 189, 190, 191.) X. REPAIR OF CROWNS AND BRIDGES 1. FOR TEMPORARY USE Crowns and bridges which have been taken off can be re- paired for temporary use, while the new bridge is nnder con- struction. There is no need for the patient to go without the crown or bridge teeth, as it is a simple matter to fix old bridges so that they will fill the spaces and spare the patient objection- able appearance. For example : when crowning an incisor or bicuspid tooth, we can cut the tooth off close to the gum, with a small cross-cut fissure bur, then prepare the root for whatever crown we intend to use. Instead of sending the patient home toothless, fit a temporary tooth or crown, such as shown in Fig- ure 192, or use the tooth that was cut off, by first removing all decay, then drilling a hole for a german silver post. Cement post into the crown, and press into place while the cement is still soft. With the same cement fill up all imperfections of the tooth to be used. When the cement is set, remove the tooth with post and sandpaper the edges (Figure 192). Now dry Fig. 192. Temporary crowns. REPAIR OF CROfVNS AND BRIDGES 175 the root, put in tlie di-essiiij^, or till the apex of tlie root, and then set tlie erowu with temporary stoj>piii<^- or soft .livitta- percha. This temporary tooth or erowii will keep the ^viiii from growing over the root, which would happen if the root would not be protected with a covering. If for any reason a tooth or crown cannot be used temporarily, a covering can be con- structed of german silver by cutting a i)late the size of root almost any gauge (from 20 to 30 gauge), whatever is at hand and soldering a post through it. Set this with gutta-percha. A gutta-percha plug can also be used for this purjiose, as follows: Shape a jjiece of pink base plate gutta-percha (coiic shape), dry the root and force it into the canal witli a suital)l( instrument. When the point is firmly held in the canal, i)res:- an extending ball over the whole surface of the tooth. In re- gard to replacing old bridges for tenqjorary wear, see I'igures 193 and 194. The post of the cuspid crown was cut off tlirougii Fig. 193. Old crowns and bridges after thev have been taken off. the band from the labial side. The gold crown was split open from the palatal side, and after the cuspid and molar roots were prepared for the new crowns, the old bridge, after boiling 176 CROfFA^S AND BRIDGES it in acid, and a new x^ost with a shoulder, is cemented in the cap without necessitating the drilling of a hole into the gold. While the cement was still soft, the bridge was placed into the position on the root. After the cement had set, the bridge was removed, all surplus cement taken away, and after drying the cuspid and molar roots the bridge was set with temporary stop- ping. (The split of the molar crown was only drawn together, and burnished, but not soldered.) Figure 194 shows two gold Fig. 194. Old bridges with posts cemented into crowns and used temporarily till new bridges were constructed. These bridges were set with temporary stopping. crowns with cemented pins, both teeth having been cut off. It was set with temporary stopping, with post cemented in bicus- pid gold crowns, and used temporarily to protect the roots, dur- ing the construction of new bridge. Very often a broken post of a Richmond crown can be re- placed without soldering, by drilling a hole into the bulk of gold, and cementing a new post into same instead of soldering. The principle is the same as with a detached post crown. REPAIR OF CROWNS AND BRIDGES 177 2. REPAIR OF GR(3WNS AND BRIDGES FOR PERMANENT USE Before removing a crown or bridge consider \vliellier you are going to use it only for a temporary aijpliance, till the ncAv bridge is made, or whether yon want to repair it for jjermanent nse. In the latter case you want to be careful Avhen cutting the crowns, so as to make the repair as easy as fjossible. All metal crowns are best cut on the buccal side, while banded jjost crowns can be removed easily, if we cut from the lingual side into the cap, using a new small round bur. In this fashion, we cut off the post from the cap and also remove \yAYt of the cement. After removing the bridge, Ave repair the all-metaj crowns by burnishing them in place, Avaxing a piece of plati- num foil in the inside. After investing, floAv solder over the cut part. For banded croAvns, fit a ucav post, which extends through sufficiently far to get the relation, wax it in place Avith sticky Avax, or take a plaster impression. Invest and solder. To cut the buccal side of a gold crown, try your wedge cutter. It does it better than most crown slitters. To extract a broken post from the root of the tooth, one can use the S. S. White's post extractor, or the Giant post puller, or Fig. 195. S. S. White's and the Giant post pullers. similar device. With a small round bur cut around the post till there is sufficient space to take hold of it with one of the described instruments. A post can also be removed by drilling with a new No. ^ round bur, around the post dowuAvards, along side of post, stay in close contact with the post, drilling part 178 CROWNS AND BRIDGES of the post, there is no danger in perforating the root. Should the post be at one side of the root, one can easily drill down on the other, finally jjushing it to the side, in the newly drilled hole, and then removing it. Broken Steele, Goslee teeth or facings can often be replaced without taking the bridge off. To repair facings we have the following metliods : 1. Ash's repair outfit. 2. Steele repair outfit. 3. Bryant repair outfit. 4. Another method. r~^ -^ 83 Fig. 196. Ash repair facings. 1. ASH'S REPAIR FACINGS a. If a pin facing is broken and both pins (cross pins) arc left in the backing, simply cement a repair facing on as de- scribed below. b. If one pin is lu'oken, the other remaining in the backing, cut off the standing pin, grind the backing flat with a small car- borundum i^oint, drill a liole in the centre of the backing Avith the Ash rei)air outfit, remove the burred edge formed by the drill, with the countersinking tool, tap the hole with the small tap, follow on with the large tap, again clear away the burred REPAIR Of CROfVNS AND BRIDGES 179 edge with the countersinking tool, fix the Ash stud selected in holder, and screw it into position rij^lit up to tlie shoulder. Select a repaii- faciii'' of llic same sv/At as the brokeii-off tooth, remove all traces of wax from it, grind it to place, thor- oughly cleanse it; mix crown and l)riar in the other half of the flask (Figure 224A). This gold bar is necessary, as rubber plates of this type are weak in front. CASE VI Two crowns to show how to overcome a wide space of the median line. A, showing the front; L>, the back of two central crowns (a practical case). These crowns, one a Richmond, the other a banded porcelain crown, filled the big space that was between the central roots, and gave satisfaction to the patients for many years. Fig. 225. Extra wide crowns to fill space of median line. CASE VII PORCELAIN ROOT DUMMIES Supplies with porcelain roots give good satisfaction to the patient and operator. Figure 226 shows right side superior Fig. 226. Model showing effect of lateral tooth dummy with porcelain root after six years. 198 CROWNS AND BRIDGES Fig. 227. Radiograph of same case. bridge; the bicuspid and cuspid roots carry Riclimond crowns, witli lateral dummy attached. The lateral dummy with a porcelain root shows after six years no irritation, or absorption of gum, as shown in Figures 226 and 227. The operation is as follows : Take a radiograph of the teeth involved in the bridge. Take a plaster impression and bite. Make an articulated model. Cut away the plaster tooth and carve (with the aid of the radiograph) the depth of the root in the model. Shellac model, carve a facing or slotted tooth with root, (Figure 228), using high fusing porcelain body. .V' A B Fig. 228. A, slotted porcelain tooth with root. B, pin facing with root. Finish the abutments next to the tooth or teeth that are to be extracted, and to be replaced with porcelain root dummies first. PRACTICAL CASES 199 Then take a wax 1)ite and ])]aster ]'iii])i-('ssi(»i). Now extract the bad tooth, and place it, with the abutments, into the plaster impression. Fig. 229. Fractured lateral root and crown. In case of a split root often caused by a post crown (Figure 226), put this post crown back on to the extracted split root, and put this with the bridge abutments back into the plaster impression. > Fig. 230. Gold inlay, with post carrying lateral dummy with porcelain root as per Figure 223A. 200 CROWNS AND BRIDGES Make articulated model. Eeniove from the model the extracted tooth or split root. Fit into the socket a hand-carved porcelain root clnmm}'. (Figure 228.) Fit a gold backing to facing (Figure 228A), or gold box with post to slotted tooth (Figure 228B) ; wax same to the abutments. Invest, solder and finish in the usual way. The bridge should be finished and set the same day when the root is extracted, as this will facilitate the placing of the porcelain root. The porcelain is received very favorably by the tissue, and therefore no inflammation and absorption is ex- perienced. CASE VI I r FULL UPPER— FIXED BRIDGE Fig. 231. Crown and Bridge Case VIII, before treatment. Showing a closed bite due to poor bridge construction. These bridges were made without chewing surfaces (see Fig. 232), allowing the bite to close, forc- ing the bridges apart and thereby loosening the bridge abutments. PRACTICAL CASES 201 Fig. 232. Crown and Bridge Case VII T, l)efore treatment. The left superior bridge is supported by the cuspid and molar. The right superior bridge by the two laterals and molar. Fig. 233. Crown and Bridge Case VIII, after treatment. Showing the new bridge with raised bite under construction. At tliig stage the bridge is shown ready for the final assembling of the three parts : lateral to lateral and cuspid to molar for each side. When soldered to the three root caps with posts and the two all-metal molar crowns this will complete a full upper fixed bridge. Facings and Steele Posteriors in gold boxes were used for dummies with two close bite gold cusps on the left bicuspids. These cusps had to be used to overcome the close bite in that region, and were constructed as shown in Fig. 124B. 202 CROWNS AND BRIDGES CASE IX FIXED BRIDGES Fig. 234. Crown and Bridge Case IX, before treatment. Fig. 235. Crown and Bridge Case IX, after treatment. PRACTICAL CASES 203 Fig. 236. Crown and Bridge Case IX. Showing the lower, before treatment. Fig. 237. Crown and Bridge Case IX. Showing the lower, after treatment, with two sanitary bridges. 204 CROWNS AND BRIDGES Fig. 238. Crown and Bridge Case IX. Showing the upper, before treatment. Fig. 239. Crown and Bridge Case IX. Showing the upper after treatment, with four anterior porcelain crowns anc two cuspid to molar self-cleansing bridges. PRACnCAL CASES 205 Fig. 240. Crown and Bridge Case IX, before treat ment. Fig. 241. Crown and Bridge Case IX, after treatment. 206 CROWNS AND BRIDGES CASE X FlXliD BRIDGES Fig. 242. Crown and Bridge Case X, before treatment. Fig. 243. Crown and Bridge Case X, after treatment. PRACTICAL CASES 207 i' Fig. 244. Crown and Bridge Case X, before treatment. Fig. 245. Crown and Bridge Case X, after treatment. 208 CROWNS AND BRIDGES Fig. 246. Crown and Bridge Case X, before treatment. Fig. 247. Crown and Bridge Case X, after treatment. Showing lower sanitary bridge with porcelain tooth dummy in box, carried by a biscuspid and molar gold inlay with post abutments. PRJCTICAL CIS US 209 Fig. 248. Crown and Bridge Case X, before treatment. Showing a molar dummy carried by an all-metal bicuspid and molar crown. The dununy is short and sets in to accommodate the elongated lower six-year molar. Compare this with Fig. 242. Fig. 249. Crown and Bridge Case X, after treatment. The lower six-year molar cut down and finished on top with a porcelain inlay. The upper bridge is constructed of three Davis l)icuspid crown type porcelain teeth, carried by the first bicuspid root with a platinum cap and post and an all- metal molar crown. The mesial corner of the cuspid is built out with porcelain. 210 CROWNS AND BRIDGES CASE XI FIXED BRIDGES Fig. 250. Crown and Bridge Case XI, before treatment. Showing close bite. Fig. 251. Crown and Bridge Case XI, after treatment. Showing raised bite. PRA C TI CA L CA SES 211 Fig. 252. Crown and Bridge Case XI, after treatment. Showing bridge in place. Fig. 253. Crown and Bridge Case XI, after treatment. Showing bridge in place. 212 CROWNS AND BRIDGES Fig. 254. Crown and Bridge Case XI, after treatment. Finished case. PRACTICAL CASES 213 CASE XII FIXED BRIDGES Fig. 255. Crown and Bridge Case XII, before treatment. Fig. 256. Crown and Bridge Case XII, after treatment. Showing bridges with porcelain teeth in boxes in place. 214 CROWNS AND BRIDGES CASE XIII FIXED UPPER AND REMOVABLE LOWER BRIDGES Fig. 257. Crown and Bridge Case XIII, before treatment. The central and laterals are badly affected by pyorrhoea. Fig. 258. Crown and Bridge Case XIII, after treatment. With a fixed bridge in place. PR.ICTICAL CASES 215 Fig. 259. Crown and Bridge Case XIII, Note the amount of tissue lost on the labial side between the cuspids. Fig. 260. Crown and Bridge Case XIII. The lost tissue between the cuspids has Ijecn replaced by two porcelain gum blocks (stock teeth) with double backings soldered to the adjoining Richmond crowns. 216 CROWNS AND BRIDGES F^G. 261. Crown and Bridge Case XIII, before treatment. The last lower molar on the left side was badly abscessed. P^ ^ ^^m .ail^fc^^ ^ M Fig. 262. Crown and Bridge Case XIII, after treatment. Showing removable bridge in place. PRACTICAL CASES 217 ^^^^^^^T^^^^^^ i^V| WT m ""^^l ^^ ■ ■ V ^^J Fig. 263. Crown and Bridge Case XIII. Showing gold frame in place. Fig. 264. Crown and Bridge Case XIII. Showing under side of the removable lower bridge with two Gihnore attach- ments in place. 218 CROWNS AND BRIDGES Fig. 265. Crown and Bridge Case XIII, before treatment. Pencil marks on model show teeth to be extracted. Fig 266. Crown and Bridge Case XIII, after treatment. With the upper fixed bridge and lower removable bridge in place. INDEX Acid mouth, 15 Adjustments, 76 Advice, operator's, 12 After-effects, 59 All-porcelain crowns, 78 Anaemia (deep), 48 Anaesthesia, Oral, 44 Ash's bridge sj^stem, 145 Ash repair facings, 178 outfit, 178 Attachment, dove-tail, 144 Gilmore, 146 Morgan, 169 Roach, 168 Bridges, assembling, 137 extension, 160 fixed, 119 full, 156 Morgan attachments, 169 removable, 144-218 removable, with Gilmore at- tachments, 145 Roach attachments, 168 short, 158 with lingual bar, 160 with vault bar, 158 Building up decayed or broken down teeth, 43 Burnished caps, banded abutments, 122 banded crowns, 95 B Backing of teeth, 64 Banded crown abutments, 122 Banded crowns, 92 Base for banded abutments, 122 crowns, 93 Box for Goslee tooth, 99 Bridge cases, classification, 13 case on articulator, 63 extensions, 144 gold chewing surface, 138 Goslee teeth, 136 individual saddles, 143 interlocking, 144 porcelain saddle, 142 repairs, 174, 180 sanitary, 137 self-cleansing, 138 study of cases, 11 with continuous saddle, 140 Bridge work, abutments for fixed, 119 supplies, 126 Care of bridges, ^^ Cases, normal and abnormal, 48 Cast cusps, 107-126 Casting, 70 Cast supplies, 127 Cementing, 75 Cement for setting crown, 124, 126 Chewing surface, gold, 137 porcelain, 138 Classification, 13 Closed bite, 27 Conductive method, 54 Crowns, all metal, 102 detached post, 81 hand carved, 81 half, with post, 123 jacket, 78 open- face (glove fit), 102 porcelain, backed with plati- num base, 88 porcelain, with burnished cap, direct method, 95 220 INDEX Crowns, porcelain, with cast base, 89 cast base, direct method, 89 cast base, indirect method, 90 detached post crowns, 98 facings, 97 Goslee teeth, 100 soldered cap, direct meth- od, 93 Steele teeth, 101 swaged cap, indirect meth- od, 96 Crowns, seamless pressed, 108 cast cusps, 107 Evslin teeth, 136 facing soldered in, 118 Morgan attachments, 171 Roach attachments, 168 seamless swaged, 113 staple, 124 stock, 82 swaged cusps, 106 temporary, 174 to fill wide space of median line, 197 two-piece, 105 two-piece, all metal, 105 Cusps, swaged, 126 D Deep anaemia, 48 Dentin, treatment for hypersensitive, 60 Detached post crown, 81-130 Devitalization, 37 Direct method, burnished caps, 93 cast base, 89 soldered caps, 93 Double backings, 128 Dovetail attachment, 144 Drugs, 41 Dummies, supplies for bridgework, 126-197 Effects, after-, 59 Evslin teeth, 136 bridge meter, 183 Examination, 11 Exodontia, 37 Extension bridges, 144-160 Face, harmony of the, 29 Facings, 67, 97-118, 126 Fear, 59 File method for root preparation, 83 Files, root, 86 Fillings, contour, 22 Final adjusting crowns and bridges, 76 Fischer syringes, 44 Fitting gutta-percha base, 85 Fixed bridges, 119, 185, 189, 192, 194, 197, 200, 202, 206, 210 Foundation, 9 Forced out of line, 30 Fractured root, 199 G Gold, 72 Gold, Alexander, 68 backings, 66 Gold casting, 70 crowns, 102-113 filling contour, 22 foil, 67 plate, 93 plating, 73 plating outfit, 74 platinized wire, 147 solder, 67 Grinding porcelain teeth, 64. 187 Gum blocks, 19, 215 Gutta-percha base, 85 H Harvard Dental School cases, 31, 189 Heat the case, 68 Hypersensitive dentin, 60 I Inlay abutments, 119 M.O.D., 119 with posts, 119 IXDEX 22\ Injcctiiiii, lUiccinator, 57 labial side ui lower incisors, 52 infra-orl,ital, 58 incisive, 58 palatal and linj4ual sides, 52 post palatine, 59 Pterygo-mandibular, 54 side of maxillary teeth, 51 Zygomatic, 57 Instruction to patients, 76 Tnstnimentarium, 44 Inter-locking two-piccc bridges, 114 Introduction, 9 Irregular teetli. .33 N Xcedle, 49 Neothesin, 60 Nerve, Buccinator, 57 Nerves, posterior superior alveolar, 58 Normal occlusion, 20 Novocain, 47 O Occlusion, 20 Open-face crown, 102 Oral anaesthesia, 44 Jacket crown, 78 Jar for syringe, 45 Jaw, lower, 51 K Knowledge received, 10 Lack of contact points, 22 Lateral, porcelain dummy with root, 198 Local anaesthesia, 44 M Mal-occlusion, 21 Mandibular protrusion, 29 Manipulation, general, 61 Maxillary injection, 51 protrusion, 29 Metal abutments, 123 Method facing repairs, another, 182 Methods, direct, 89, 93 indirect, 89, 96 Mineral stains, 182 Models, 12 Mouths, treatment of, 37 Morgan attachments, 169 Mounting crown and bridge case on articulator, 63 Pathological conditions, 13 Pieso's, 145 Plating bridges with pure gold, 73 Platinum plate, 88 post, half-crown, 123 saddle, 144 staple, 124 Polishing, 72 Porcelain crowns, 78, 90 Position of operator, 84 Posterior Goslee teeth, 135 Steele teeth, 131 Post fitting to root, 83 with inlays, 119, 120 Post-palatine injection, 59 Posts, Davis straight and offset centre, 87 Preliminary treatment, 37 Preparing for insertion, 49 Prophylactic treatment, 37 Pterygo-mandibular injection, 54 Pulp removal, 52, 59 Pyorrhoeatic conditions, 15 Pyorrhoea treatment, 37 R Replaceable crowns, Goslee, 135 facings, 101, 136 Removable bridge, 145 Gilmore attachment, 145-160, 214-218 Roach attachments, 168 222 INDEX Removable bridge, Morgan attach ments, 169 Repair bridges, 174, 180 facings, Ash, 179 Richmond crown, 93, 97 Root, impression of, 96 preparation, 93 porcelain, 198 Saddle bridges, 140 with continuous saddle, 140 extension with saddle, 144 with individual saddle, 143 with porcelain saddle, 142 with removable saddle, 145, 169 Sanitary bridges, 137 Seamless crowns, 102 pressed, 108 swaged, 113 Self-cleansing bridges, 138 Selecting teeth, 64 shade, 61 Septic roots, 13 Soldering, 69 Soldering bridge in sections, 69 Soldered caps, 93 Special instruments, 182 Split root, 199 Staple crown, 124 Steele posterior, 131 Steele repair outfit, 179 Steele teeth, 101 Supplies for banded crowns, 97 Swaged caps, 96 Swaged cusps, 106 Syringes, 46 Tablets of Novocain, 47 Taggart wax, 120 Taking bite, 61 impression, 61 Technical manipulation, 61 Teeth, condition of, 13 elongated, 24 Evslin, 136 Goslee, 100 irregularly arranged, Zi Steele, 101 tipped forward, 22 temporary retained, 26 treatment of, 37 wandering, 30 Treatment for hypersensitive dentine, 60 U Use of Amalgam, 43 Antiflux, 131 bridge meter, 183 bridge repair tools, 180 stains, 182 s wager, 111, 134 V Vulcanite rubber, 60 W Wax, Taggert's, Kerr's, 120 Window or open-face crown, 104 With cast cusps, 107 detached post crown, 98, 122 facings, 97, 122 gold chewing surface, 137 Goslee teeth, 100, 122 porcelain chewing surface, 138 Steele teeth, 101, 122 swaged cusps, 106 LIST OF ILLUSTRATIONS FIG. PAGE 1. Radiographs showing perforalion of roots with posts extending through same 11 2. Model and radiograph of distal root of a six-year molar carrying a crown with extension 14 3. Radiograph showing pathological conditions of the teeth .... 14 4. Radiograph showing pyorrhoeatic conditions of the roots .... 15 5. Bridge splint 16 6. Radiograph of bridge splint in place .... 17 7. Lower bridge of two open-face crowns with gum block .... 19 8. Two bridges with gum blocks 19 9. Plain and gum teeth 19 10. Bridge case with normal occlusion 20 11. Two models showing sufficient occlusion 21 12. Mal-occlusion. Before and after treatment 21 13. Mal-occlusion. Model 22 14. Mal-occlusion. Model 23 15. Radiographs showing lack of contact points. Before and after treat- ment 23 16. Radiograph showing contact points restored b}- crowns 23 17. Mal-occlusion. Molar tipped forward 24 18. Mal-occlusion. Bridge with inter-locking device 24 19. Mal-occlusion. Bridge with inlay abutments 25 20. Mal-occlusion. Upper bicuspid is elongated caused by loss of lower teeth 25 21. Radiograph. Right lateral incisor a temporary tooth 26 22. Radiograph showing absorption of the roots of two temporary teeth 26 23. Showing unerupted cuspids under bridges 2/ 24. Mal-occlusion, closed bite. Bite has closed to such an extent, the upper incisors have worn down 27 224 LIST OF ILLUSTRATIONS FIG. PAGE 25. Mal-occlusion, closed bite, lower jaw. Before and after treatment 28 26. Mal-occlusion, closed bite. Front view 28 27. Mal-occlusion, closed bite. Left side views show conditions before and after restoration 29 28. Mal-occlusion, closed bite. Right side of same case 29 29. Mal-occlusion. Incisors pushed out on account of closing bite . . 30 30. Mal-occlusion, mandibular protrusion 31 31. Mal-occlusion, maxillary protrusion 32 32. Mal-occlusion, upper incisors are projecting 32 2>2). Mal-occlusion, wandering teeth 33 34. Mal-occlusion. Spreading of the two central incisors 34 35. Mal-occlusion. A shows the position of the upper lateral and cuspid 34 36. Mal-occlusion. One lateral incisor absent, front teeth of irregular length 35 2)7. Mal-occlusion. Case with very irregular teeth 35 38. Radiographs showing cases where teeth have been crowned without devitalizing the pulps 38 39. Radiographs showing chronic abscesses on roots of upper teeth, used as abutments, root canals not having been properly filled ... 39 40. Radiographs showing chronic abscesses on roots of lower teeth 39 41. Series of radiographs showing treatment and filling of root canals of teeth to be used as bridge abutments 40 42. Radiograph of second bicuspid and first molar with chronic abscesses 41 43. Showing bent root of a lower second bicuspid 41 44. Radiographs of receded pulps and constricted chambers, found in advanced age 42 45. Radiographs showing large pulp chambers, found in young teeth . 42 46. Radiographs showing abnormal branching of root canals .... 42 47. Instruments for local anaesthesia 45 48. Syringes 46 49. Large and small dissolving cups 46 50. Skulls showing the small foramina in the alveolar process ... 50 51. Position of the operator when injecting 51 52. Radiograph showing the infiltration method for an upper cuspid . . 52 LIST (Jf ILLUSTRJTIOXS 225 FIG. I'AGE 53. Horizontal section through iunnan head 53 54. Technique of inserting needle for ptcrygo-mandiljular injection . . 55 55. Sulcus mandihularis with needle 56 56. Photograph showing posterior superior alveolar branches .... 57 57. Palate of an adult . . 58 58. Plaster impressions after washing trays and broken pieces with hot water 62 59. Plaster impressions after pieces are put back in place and held by sticky wa.x 62 60. Plaster impressions after casting, showing how impression was cut in mouth 62 61. Case mounted on anatomical articulator by means of a face bow . . 64 62. Facings with single and double backings 65 63. Soldering two backings in the flame 66 64. Showing a Goslee tooth saddle bridge invested ready to solder . . 68 65. Showing a full upper bridge 69 66. Gold-plating outfit of simple construction 74 67A, 67B, 67C. Steps for jacket crown 80 68. File methods for root preparation 83 69A, 69B. Position of operator filing a left upper bicuspid root and a lower incisor root 84 70. Detached post crown with gutta-percha washer 85 71. A root file, also a toothbrush handle with root-file grooves ... 86 72. Root preparation for detached post crown 87 73. Shows straight and offset centre post 87 74. Steps for making porcelain baked crown, platinum base .... 88 75. Porcelain crown with cast base. Direct method 90 76. Porcelain crown with cast base. Indirect method 91 77. Steps for making band for soldered cap 93 78. Fitting of top to band and soldering post 94 79. Dr. Hovestadt's special plate punch 94 80. Shows the use of plate punch 94 81. Hand Inirnished top with post. Finished crown 95 82. .Steps showing the making of swaged root caps 96 226 LIST OF ILLUSTRATIONS FIG. PAGE 83. Banded crown with facing 98 84. Soldered cap with detached post crown 98 85. Swaged cap and box with detached post crown 99 86. Banded crown with Goslee tooth 100 87. Banded crowns with Steele facings . 101 88. Steps for seamless open-face crowns (glove fit) 102 89. Die with handle 103 90. Steps continued for open-face crown (glove fit) 104 91. Steps for two-piece all-metal crown, swaged cusps 105 92. Steps for two-piece all-metal crown, cast cusps 107 93. Steps continued from Figure 92 107 94. Taking bite with copper band in position 108 95. Crown contoured to copper band . 108 96. Shows split tray with moldine to take impression of crown . . . 109 97. Split tray in position 109 98. Tray after removal and closed 110 99. Metal die and shell 110 100. Wooden blocks showing" imprints of metal die and swager . . . 110 101. Diagram of swager ..Ill 102. Swaging of crown over die into wood block 112 103. Melting out the metal from the crown 112 104. Finished crown 113 105. Seamless all-metal crown. Bridge method. Impression with bands 114 106. Bands on articulated model 114 107. Crowns contoured and articulated 114 108. Ready to cast 114 109. Casting to die . 115 110. Building fusible metal to edge of bands ' . . . 115 111. Knocking off metal from ring 116 112. Splitting of die 116 113. Pressing of seamelss shell 117 114. Shows marking of swaged crown to conform to cervical margin, de- termined by trial band 117 LIST or ILIA'STRAI'KJXS 227 FIG. i'AGK 115. Shows curved scissors for Iriniming crowns and l)ands .... 117 116. Steps for crowns with porcelain facing 118 117. Tooth preparations for inlay abutments 120 118. Steps for bridge with inlay abutments 12'i 119. Half-crown with post 123 120. Steps for making staple crowns 125 121. Model on articlator for cast supplies 127 122. Supplies before and after casting 127 123. Facings with single and double backings 128 124. Facings with swaged cusps 129 125. Bridge with supplies of anterior Steele teeth 130 126. Steps for making Steele anterior crown 131 127. Steele anti-flux 131 128. Painting of backing with Steele anti-flux 132 129. Right and wrong way of filing backings 132 130. Filing to remove obstructions '. . . 132 131. Bridges with Steele posteriors 132 132. Soldering extension to backing 133 133. Fitting to tooth 133 134. Steps for making box for Steele posteriors 133 135. Bridge with short teeth and short gold crown abutments .... 133 136. Steele posterior molar with slice cut from the distal side .... 134 137. Bridge with wash space and freedom of festoon next to crown abut- ments and dummies 134 138. Anterior and posterior Goslee teeth 135 139. Steps to show making of boxes for Goslee teeth, or other porcelain crowns ' . . . . 135 140. Anterior Goslee bridge : 136 141. Posterior Goslee bridge 136 142. Evslin interchangeable teeth for crown and bridge work .... 136 143. Soldering of casting to all metal abutments 137 144. Top view of sanitary bridge : . . . 137 145. Sanitary bridge with gold casting 137 228 LIST OF ILLUSTRATIONS FIG. i'AGE 146. Sanitary bridge with porcelain chewing surface 138 147. Self-cleansing bridge showing wash spaces ... 140 148. Saddle bridge. Teeth in core before boxing 141 149. Saddle bridge. Teeth boxed 141 150. Saddle and boxes invested ready for solder 141 151. Saddle bridge, before and after cementing supplies 142 152. Shows a banded porcelain molar crown and bicuspid dummy . . 142 153. Hand-carved porcelain blocks with porcelain saddles 143 154. Extension bridge from front and back 144 155. Plaster impression of four abutments 147 156. Plaster model with four abutments 148 157. Abutments removed from model to solder wire frame 149 158. Finished frame in position 149 159. Finished frame for another case 150 160. Frame and Gilmore Attachments in position on flasked model . . 151 161. Other half of flask 151 162. A full lower Gilmore denture 152 163. A full lower Gilmore denture after treatment 153 164. Full upper Gilmore denture 153 165. Another full lower Gilmore case. Finished frame on model . . 154 166. Full upper Gilmore denture. Case before treatment 155 167. Same case with finished frame in position ........ 155 168. A plaster model of back of finished denture 156 169. Case of a patient seventy-three years of age 157 170. Full lower, with two roots and two Gilmore attachments .... 158 171. Full lower, with one root, using two Gilmore attachments . . . 158 172. Anterior fixed and posterior removable bridge with Gilmore attach- ments 160 173. Partial removable bridges with three Gilmore clasps 161 174. Removable partial bridge 162 175. Partial lower removable gold denture held with one Gilmore attach- ment 163 176. Removable bridge with vault bar 164 LIST Ol' ILLUSTIUTIONS 229 K[G. PACt: 177. Removable bridge held Ity three Gihiiore attachments 164 178. Partial removable bridge with vault bar, two Gilmore attachment? 165 179. Partial removable bridge with lingual bar and two Gilmore attach- ments 165 180. Removable extension bridge for one side 166 181. Top view of finished case No. 180 166 182. Model with extension wires running parallel ; in this case the den- ture with Gilmore attachments is liable to slide back .... 167 183. Different styles of Gilmore Adjustable Attachments 167 184. Roach attachments for removable bridges 168 185. Morgan attachments for removable bridges 170 186. Jig for Morgan attachments 170 187. Morgan attachments soldered to all-metal crowns 171 188. Morgan attachments used on various crowns 171 189. Finished case of Figure 187 172 190. Saddle with single Morgan attachments 172 191. Lower denture with Morgan attachments 173 192. Temporary crowns 174 193. Old crowns and bridges after they have been taken off . . . . 175 194. Old bridges with posts cemented into crowns and used temporarily 176 195. S. S. White's and the Giant post pullers 177 196. Ash repair facings 178 197A. Steele repair outfit 179 197B. Different steps to repair a broken pin facing 180 198A, 198B. Bryant repair outfit 180, 181 199. Mineral stains and stained teeth 182 200. Measuring distance with bridge meter 183 201. Parallelism obtained with the Evslin bridge meter 183 202. Shows condition of mouth 185 203. Radiographs of the roots 185 204. Shows impression of alnitments 1S6 205. Plaster model with abutments in place 186 206. Articulated models with face bow relation 187 230 LIST OF ILLUSTRATIONS FIG. PAGE 207. Bridge teeth waxed for trial 187 208A. Shows crowns held in plaster core 188 208B. Shows crowns boxed 188 209. Sections of tooth boxes invested and ready for soldering .... 188 210. Sections united to abutments 189 211. Finished fixed bridge with teeth cemented into boxes 189 212. 213. Harvard Dental School case, before treatment 190 214. Radiograph revealing absence of permanent teeth, same case . . . 191 215. Same case, after treatment 191 216. Pyorrhoea case, before and after treatment 192 217. Same case, presenting a closed bite. Bite was raised with fixed bridges 192 218. Cast inlays for same case 193 219. Same case, before and after treatment 193 220. Protruding lower teeth, before treatment ; model and radiograph . 194 221. Bridge frame, same case 194 222A, 222B. Shows frame on model and radiograph of frame on roots . 195 223. Shows upright position of artificial teeth •. . . 196 224. The case fiasked 196 225. Extra wide crowns to fill space of median line 197 226. Model showing efifect of lateral tooth dummy with porcelain root after six years 197 227. Radiograph of same case 198 228. Slotted porcelain tooth with root and pin facing with root . . . 198 229. Fractured lateral root and crown 199 230. Gold inla}', with post carrying lateral dummy with porcelain root . 199 231. Crown and Bridge Case VIII, before treatment, showing a closed bite due to poor bridge construction . 200 232. Case A^III, before treatment 201 233. Same case, after treatment 201 234. Case IX, before treatment 202 235. Case IX, after treatment 202 236. Case IX, showing lower 203 LIST OF ILLUSTRATIONS 231 FIG. J'AGE 237. Case IX, showing Irjwcr, after treatment; two sanitary Ijridges . . 203 238. Case IX, showing upper, before treatment 204 239. Case IX, after treatment 204 240. Case IX, before treatment 205 241. Case IX, after treatment 205 242. Case X, before treatment 206 243. Case X, after treatment 206 244. Case X, before treatment 207 245. Case X, after treatment 207 246. Case X, before treatment 208 247. Case X, after treatment 208 248. Case X, before treatment 209 249. Case X, after treatment 209 250. Case XI, before treatment, showing close bite 210 251. Case XI, after treatment, showing raised bite 210 252. Case XI, showing bridge in place 211 253. Case XI, showing bridge in place 211 254. Case XI, finished 212 255. Case XII, before treatment 213 256. Case XII, after treatment 213 257. Case XIII, before treatment 214 258. Case XIII, after treatment 214 259. Case XIII 215 260. Case XIII 215 261. Case XIII, before treatment 216 262. Case XIII, after treatment 216 263. Case XIII 217 264. Case XIII . 217 265. Case XIII, before treatment 218 266. Case XIII, after treatment 218 COLUMBIA UNIVERSITY LIBRARY This book is due on the date indicated below, or at the expiration of a definite period after the date of borrowing, FAS provided by the rules of the Library or by special ar- rangement with the Librarian in charge. DATE BORROWED DATE DUE DATE BORROWED DATE DUE APt^lO 19 it C28(239)MI00 1 COLUMBIA UNIVERSITY LIBRARIES (hsi.stx) RK 666 H82 C.1 PrinOiplf;'. mIK: !';i.tl'!;l;l,l: (jf 'MUnW ^illlj Ij 2002449439 '/^.,^/p/'^, '^U '/•^