Restoration of endodontically treated posterior teeth with amalgam Donald R. Brown, D.D.S.,* Wayne W. Barkmeier, D.D.S., M.S.,” * and Ronald W. Anderson, D.D.S., M.S. * * * USAF Hospital, Chanute Air Force Base. Ill.
treated posteriAh e restoration of endodontically or teeth presents a unique challenge for the restorative dentist. Endodontically treated teeth are weakened by removal of the roof of the pulp chamber and canal enlargement and are more susceptible to fracture than vital teeth.‘-:’ Endodontically treated teeth must be restored to withstand both vertical and lateral forces to resist fracture, and a cast restoration is usually considered ideal, Weine’ suggested that a cast crown or onlay for endodontically treated teeth must be combined with a dowel and core to provide “coronal-radicular stabilization.” A silver amalgam restoration is usually not considered when restoring endodontically treated posterior teeth. Th e purpose of this article is to discuss the pin-retained amalgam restoration as an acceptable alternative to the cast restoration and present a technique for the restoration of endodontically treated posterior teeth. The pin-amalgam restoration with complete cusp protection will adequately restore the coronal portion of endodontically treated teeth and resist both vertical and lateral forces to prevent fracture.
Questionable endodontic or periodontic prognosis. The treatment of some pulpal pathoses may have ideal
prognosis.
Repair
may
involve
The views expressed herein are those of the authors and do not necessarily reflect the views of the United States Air Force or the Department of Defense. *General Practice Resident. **Chief, Operative Dentistry. ***Chief. Endodontics.
40
Diflicult
teeth to isolate for endodontic treatment.
Mutilated teeth with extensive coronal destruction arc often difficult to isolate for endodontic treatment. A pin-retained amalgam, prior to endodontic treatment, will facilitate rubber dam application and help prevent contamination during endodontic treatment. Economic factors. Economic considerations may be a deciding factor in determining the type of restoration proposed for endodontically treated teeth. A patient may be well motivated, yet cannot absorb the cost of a cast restoration. A pin-amalgam restoration may serve as a long-term restoration or as an interim restoration until economic factors are more favorable.
Disabled, handicapped patients and/or medical conditions that preclude multiple office visits.
INDICATIONS FOR PIN-AMALGAM RESTORATION OF POSTERIOR ENDODONTICALLY TREATED TEETH
a less than
several months to 1 year. Cast gold restorations are not indicated when the prognosis is questionable. However, unless the tooth is restored, failure may occur due to fracture, caries, or extension of periodontal disease caused by poor coronal contour and/or occlusal discrepancies. The pin-retained amalgam restoration can serve as an interim restoration and later as a core for a complete crown when the endodontic or periodontal prognosis improves.
Special considerations are frequently necessary for this group of patients. They may not be capable of multiple office visits or long appointments. The pin-amalgam restoration offers an avenue of treatment for endodontically treated teeth with a minimum of appointment time. High caries index. Endodontic treatment may be accomplished for patients with a dental history of extensive caries. In such patients a pin-retained amalgam restoration for endodontically treated posterior teeth should be considered. Cements used for cast restorations are soluble and may dissolve,
JANUARY
1979
VOLUME
41
NUMBER 1
AMALGAM
RESTORATIONS
OF ENDODONTICALLY
TREATED
TEETH
inviting recurrent caries for these high-risk patients6 Amalgam restorations resist recurrent caries; amalgam is not soluble and corrosion products seal the margins.’ Teeth not receptive to dowels. Amalgam restoration for endodontically treated teeth is recommended when lack of access, poor visibility, or anatomy of a canal prevents dowel fabrication.?. x Conditions that may preclude the use of a dowel are fine, narrow, short, divergent, and tortuous root canals. Dowels should also be avoided in teeth that may be conducive to root fracture. Dowels should not be used in teeth with visible fracture lines or if a cracked tooth or incomplete tooth or root fracture is suspected. TECHNICAL
PROCEDURE
Cusp reduction. Complete cusp protection requires the reduction of all cusps. A 2% to 3 mm reduction allows sufficient amalgam bulk to insure maximum strength!’ and also allows 2 mm of the pin to extend outside the cavity for amalgam retention.‘” Frequently, due to undermined cusps, existing restorations, or endodontic access, further occlusal reduction may be warranted. Unsupported enamel must be removed to prevent fracture and to expose an adequate amount of dentin to support the required number of pins necessary to achieve resistance and retention form in the preparation. Pin channel location. Although pin channel location is an important consideration, the number and location of pinholes are primarily dictated by empirical judgement. Various guidelines for pin placement have been advocated.“-” This report recommends the “rule of thumb” of one pin per cusp and two per marginal ridge.” This concept requires one pin for each reduced cusp and pin placement for each proximal cavity wall that is missing or insufficient to provide adequate retention and resistance. However, if the dentin between the proximal box and the pulp chamber is inadequate to support the buccal and lingual cusps, pins should be placed in the gingival wall even if proximal walls are present. Lateral or periodontal perforation must be avoided during pin channel preparation because this may cause loss of the tooth. Pinholes should be directed in a more pulpal direction, because penetration into the pulp chamber or canal is of no consequence for endodontically treated teeth. This pin location also facilitates tooth preparation for a
THE JOURNAL
OF PROSTHETIC
DENTISTRY
Fig. I, A and 8. A, Maxillary first premolar, temporary restoration following endodontic treatmrilt. B, ‘i‘ooth preparation, cusps reduced. cc~nented pins : four’) inserted.
cast restoration with amalgam as a core. since the pins are further from the tooth periphery and thus surrounded by a greater bulk of amalgam.’ Type of pin. A clinical technique for restoring badly mutilated crowns with cemented pins and amalgam was described by Markfey: in 1958. This cemented pin technique uses a 0.025~inch diameter pin cemented in a 0.027-inch pin channel. Markley advocated a circle of pins in a weak root or crown to bind or splint the tooth against splitting.‘, Ii Collard, Caputo, and Standlee’” suggested that pins splint weak teeth and that, in addition to the splinting, masticatory forces are more evenly distributed to the various parts of the tooth, but only when cemented pins are used. Courtade” states, “‘The endodontically treated root is strengthened and splitting of the root is prevented by using five to eight threaded steel rods in the dentin around the root canal filling.”
41
BROWN,
Fig. 1, C and D. C, Restoration finished and polished. D, Facial aspect, completed restoration. Cemented pins show no tendency to cause dentin Self-threading and friction-locked pins defects.” induce stresses that may lead to cracking and crazing of dentin.“‘-‘s These stresses must be avoided to prevent damage to endodontically treated teeth. The cemented pin is the pin of choice for restoring endodontically treated teeth. Advantages of the cemented pin technique include (1) ability to splint roots, (2) resistance and retention form for cavity preparation, and (3) no installation stresses that may induce dentinal damage. Pin channel preparation and pin insertion. Pin channel depth is an important consideration for retention and potential tooth splinting. Research is lacking in resistance to occlusal loading and splinting or reinforcing teeth against splitting as related to pin channel location and depth. Retention of cemented pins is considerably less than that of friction-locked or self-threading pins when they are compared in the laboratory.“’ Markley’ has recommended a depth range of 2 to 5 mm in
42
BARKMEIER,
AND
ANDERSON
Fig. 2, A and 8. A, Mandibular first molar. temporary restoration following endodontic treatment. B, Tooth preparation. cusps reduced, cemented pins (six) inserted. sound dentin for adequate retention of cemented pins. Pin channel depth is dependent on tooth and root morphology, but the upper limits of Markley’s recommendation should provide adequate clinical retention and tooth splinting to protect against tooth fracture. The 0.027-inch pinholes are drilled to a depth of 2 to 5 mm approximately 1 mm from the dentinoenamel junction. A sharp twist drill will prevent lateral cracks in dentin. lb Pin channels should be prepared at slow drill speed, using a single thrust motion and constant air spray to remove debris. The twist drill is aligned by the technique of paralleling the adjacent root surface with the twist drill and then preparing the pinholes with the same orientati0n.l’. 1; Following pin channel preparation a length of 0.025-inch diameter pin* is cut to allow a 2 mm length to be embedded in amalgam when the pin is ‘Star
Dental
Mfg.
Co.. Inc., Conshoshocken,
JANUARY
1979
VOLUME
Pa.
41
NUMBER
1
AMALGAM
RESTORATIONS
OF ENDODONTICALLY
TREATED
TEETH
fully seated in the pin channel. Before cementation, the pin is bent slightly to ensure its coronal portion is well within the body of the amalgam restoration. Zinc phosphate cement is mixed to the consistency required to cement an inlay and is placed in all pinholes with a lentulo spiral and slow-speed contra-angle handpiece. The channel end of the pin is then covered with cement and the pins immediately inserted and allowed to remain undisturbed until the cement has set (Figs. 1, A and B, and 2, A and B). Cavity varnish is not used in the pinholes because the retention of cemented pins is reduced by 46%. I” Utilization
In the final restoration it is always wise to consider and provide for endodontic retreatment. The coronal endodontic filling material is removed to a thickness of approximately 1 mm covering the pulpal floor. A zinc phosphate base of 1 to 2 mm is then placed. In the event endodontic retreatment is necessary, the zinc phosphate base will facilitate gaining access. All surfaces of the cavity preparation are covered with a copal resin varnish. This will seal the margins and prevent marginal microleakage under the amalgam restoration.“‘. ‘I Matrix and amalgam condensation. A matrix band retainer can be used for restoring teeth with minimal coronal destruction. However, for extensive restorations a soldered-band or copper band matrix is required.” “” Following matrix and wedge placement, the amalgam is condensed into the cavity preparation using small condensers to condense the amalgam in the proximity of the pins.“’ After condensation around the pins, large portions of amalgam can be condensed for rapid insertion.“,’ Following condensation, the wedges and matrix are removed and the restoration carved. Occlusal relationships are verified with articulating paper, and the patient is then reappointed for finishing the restoration. Finishing. The finishing appointment has three objectives. These are (1) to verify proximal contours, (2) to ensure occlusal relationships, and (3) to finish and polish the restoration. Radiographic and clinical examinations, to evaluate proximal contour and reveal any overhang of proximal amalgam, are made. The occlusal relationships are again examined and any occlusal discrepancies are corrected. The amalgam alloy restoration is then finished and polished (Figs. 1, C and D, and 2, C). Tarnish and corrosion are reduced by a
THE JOURNAL
of a base and cavity
OF PROSTHETIC
DENTISTRY
varnish.
Fig. 2C. Completed restoration of mandibular molar.
smooth polished surface, and the longevity restoration is thereby increased.”
first
of the
SUMMARY
A technique for restoring endodontically treated posterior teeth has been presented. The pin-amalgam restoration may be used as an acceptable alternative to the cast restoration for situations where a cast restoration is not indicated. REFERENCES ed 1. St. foilis, 1972,Thr 1. W&e. F. S.: EndodonticTherapy. C. \‘. Mosby Co. K. ‘I‘.: 2. Johnson, .J. K.. Schwartz, N. I.., and Blackwell, Evaluation and restoration of endodonticallv treated posterior teeth. J Am Dent Assoc 93:597. 1976. 3. Ingle, J. I.: Endodontics, ed I. Philadelphra. 1965. J.ea CPT Febiger, Publishers. 4. Rosen, H.: Operative procedures on mutilated endodontically treated teeth. .J PROSTHETDew 11:97X 196l. 5. Silverstein, W. H.: The reinforcement of weakened pulpless teeth. J PROSTHETDENT 14:372, liJ64. 6. Dawson, P. E.: Pin-retained amalgam. Dent Clin North Am 14:63, 1971. 7. Markley, M. R.: Pin reinforcement and retrntion of amalgam foundations and restorations. J Am Dent Assoc X:675, 1958. 8. Shillingburg. H. T.. Fisher, D. W., and Dewhirst, K. B.: Restoration of endodontically treated posterior teeth. J PROSTWETDEXT 24:401, 1970. 9. Charbeneau, C. T.: Principles and Practice of Operative Dentistry. Philadelphia, 1975, Lea & Febiger, Publishers. 10. M&a, J. P., Razzano, M. R., and Doyle. M. G.: Pins-A comparison of their retentive properties. LJ .4m Dent ASSOC 78:529, 1969. 11. Bales, D. J,: Operative Dentistry Notebook. \Yilford Hall USAF Medical Center, Lackland .4FB, Texas. .4ugust 1969. 12. Courtade, G. L.: Pin pointers. III. Self-threading pins. J PROSTHET DENT 20:335, 1968. treated 13. Schwartz, N. L.: Restoration of endodontically
43
BROWN,
14.
15.
posterior teeth. Read before the American Prosthodontic Society, Washington D. C., November 1974; Cited br Johnson, .J. K., Schwartz, N. L., and Blackwell, R. T.: Evaluation and restoration of endodontically treated posterior teeth. J Am Dent Assoc 93:597, 1976. Enoch, J. D., and Cochran, M. A.: Pin-retained amalgam. In Baum, I,.: Advanced Restorative Dentistry, Modern Materials and Techniques, ed 1. Philadelphia, 1973, W. B. Saunders Co. Markley, M. R.: Pin retained and reinforced restoration foundations. Dent Clin North Am March 1967, pp 229.
17.
18.
19.
Collard, E. W., Caputo, A. A., and Standlee, J. P.: Rationale for pin-retained amalgam restorations. Dent Clin Sorth Am 14:43, 1970. Courtade, G. I,.: Creating your own “dentin.” Procedures for rebuilding badly broken-down teeth. Dent Clin North Am, Nov. 1963, pp 805-822. Standlee,J. P., Collard, E. W., and Caputo, A. A.: Ijentinal defects caused by some twist drills and retentive pins. J PXOSTHET I)EN.I. 24:18.5, 1970. Moffa, J. P., Razzano, M. R., and Folio, J,: Influence of
20.
21.
22. 23.
INFORMATION
PROSTHE.I.
24.
I>em
35171,
AIVIXRSON
1976.
Phillips, K. W.: Science of Dental phia, 1973, W. H. Saunders Co.
Reprint DR.
AND
cavity varnish on microleakage and retention of variou\ pin-retaining devices. J PXOSTHIX DEXI. 20541, 19611. Going. R. E., and Massler, M.: Influence of cavity liners under amalgam restorations on penetration by radioactive isotopes. J PX0SI.HE.I. DEW 11:298. 1961. Barber, D., Lyell, J.? and Massler, M.: Effectiveness of Copal resin varnish under amalgam restorations. .J P~osru~r Drxr 14533, 1964. Gilmore, 11. W., and Lund, M. K.: Operative Dentistry, ed 2. St. Louis, 1973, The C. V. Mosby Company. Birtcil, R. F., and Venton, E. A.: Extracoronal amalgam restoration utilizing available tooth structure for retention, J
244. 16.
BARKMEIER,
ed 7. Philadel-
requests to:
WAYNE
BOYNE
Materials,
W.
BAKKMEIBR
SCHOOL
OF
DENTAL
PENCE
CREKXTON UNIVERSITY 2500 CALIFORNIA ST. OMAHA,
NEB.
68178
FOR AUTHORS
Most of the provisions of the Copyright Act of 1976 became effective on January 1, 1978. Therefore, all manuscripts must be accompanied by the following written statement, signed by one author: “The undersigned author transfers all copyright ownership of the manuscript (title of article) to The C. V. Mosby Company in the event the work is published. The undersigned author warrants that the article is original, is not under consideration by another journal, and has not been previously published. I sign for and accept responsibility for releasing this material on behalf of any and all co-authors.” Authors will be consulted, when possible, regarding republication of their material.
JANUARY
1979
VOLUME
41
NUMBER
I
treated posteriAh e restoration of endodontically or teeth presents a unique challenge for the restorative dentist. Endodontically treated teeth are weakened by removal of the roof of the pulp chamber and canal enlargement and are more susceptible to fracture than vital teeth.‘-:’ Endodontically treated teeth must be restored to withstand both vertical and lateral forces to resist fracture, and a cast restoration is usually considered ideal, Weine’ suggested that a cast crown or onlay for endodontically treated teeth must be combined with a dowel and core to provide “coronal-radicular stabilization.” A silver amalgam restoration is usually not considered when restoring endodontically treated posterior teeth. Th e purpose of this article is to discuss the pin-retained amalgam restoration as an acceptable alternative to the cast restoration and present a technique for the restoration of endodontically treated posterior teeth. The pin-amalgam restoration with complete cusp protection will adequately restore the coronal portion of endodontically treated teeth and resist both vertical and lateral forces to prevent fracture.
Questionable endodontic or periodontic prognosis. The treatment of some pulpal pathoses may have ideal
prognosis.
Repair
may
involve
The views expressed herein are those of the authors and do not necessarily reflect the views of the United States Air Force or the Department of Defense. *General Practice Resident. **Chief, Operative Dentistry. ***Chief. Endodontics.
40
Diflicult
teeth to isolate for endodontic treatment.
Mutilated teeth with extensive coronal destruction arc often difficult to isolate for endodontic treatment. A pin-retained amalgam, prior to endodontic treatment, will facilitate rubber dam application and help prevent contamination during endodontic treatment. Economic factors. Economic considerations may be a deciding factor in determining the type of restoration proposed for endodontically treated teeth. A patient may be well motivated, yet cannot absorb the cost of a cast restoration. A pin-amalgam restoration may serve as a long-term restoration or as an interim restoration until economic factors are more favorable.
Disabled, handicapped patients and/or medical conditions that preclude multiple office visits.
INDICATIONS FOR PIN-AMALGAM RESTORATION OF POSTERIOR ENDODONTICALLY TREATED TEETH
a less than
several months to 1 year. Cast gold restorations are not indicated when the prognosis is questionable. However, unless the tooth is restored, failure may occur due to fracture, caries, or extension of periodontal disease caused by poor coronal contour and/or occlusal discrepancies. The pin-retained amalgam restoration can serve as an interim restoration and later as a core for a complete crown when the endodontic or periodontal prognosis improves.
Special considerations are frequently necessary for this group of patients. They may not be capable of multiple office visits or long appointments. The pin-amalgam restoration offers an avenue of treatment for endodontically treated teeth with a minimum of appointment time. High caries index. Endodontic treatment may be accomplished for patients with a dental history of extensive caries. In such patients a pin-retained amalgam restoration for endodontically treated posterior teeth should be considered. Cements used for cast restorations are soluble and may dissolve,
JANUARY
1979
VOLUME
41
NUMBER 1
AMALGAM
RESTORATIONS
OF ENDODONTICALLY
TREATED
TEETH
inviting recurrent caries for these high-risk patients6 Amalgam restorations resist recurrent caries; amalgam is not soluble and corrosion products seal the margins.’ Teeth not receptive to dowels. Amalgam restoration for endodontically treated teeth is recommended when lack of access, poor visibility, or anatomy of a canal prevents dowel fabrication.?. x Conditions that may preclude the use of a dowel are fine, narrow, short, divergent, and tortuous root canals. Dowels should also be avoided in teeth that may be conducive to root fracture. Dowels should not be used in teeth with visible fracture lines or if a cracked tooth or incomplete tooth or root fracture is suspected. TECHNICAL
PROCEDURE
Cusp reduction. Complete cusp protection requires the reduction of all cusps. A 2% to 3 mm reduction allows sufficient amalgam bulk to insure maximum strength!’ and also allows 2 mm of the pin to extend outside the cavity for amalgam retention.‘” Frequently, due to undermined cusps, existing restorations, or endodontic access, further occlusal reduction may be warranted. Unsupported enamel must be removed to prevent fracture and to expose an adequate amount of dentin to support the required number of pins necessary to achieve resistance and retention form in the preparation. Pin channel location. Although pin channel location is an important consideration, the number and location of pinholes are primarily dictated by empirical judgement. Various guidelines for pin placement have been advocated.“-” This report recommends the “rule of thumb” of one pin per cusp and two per marginal ridge.” This concept requires one pin for each reduced cusp and pin placement for each proximal cavity wall that is missing or insufficient to provide adequate retention and resistance. However, if the dentin between the proximal box and the pulp chamber is inadequate to support the buccal and lingual cusps, pins should be placed in the gingival wall even if proximal walls are present. Lateral or periodontal perforation must be avoided during pin channel preparation because this may cause loss of the tooth. Pinholes should be directed in a more pulpal direction, because penetration into the pulp chamber or canal is of no consequence for endodontically treated teeth. This pin location also facilitates tooth preparation for a
THE JOURNAL
OF PROSTHETIC
DENTISTRY
Fig. I, A and 8. A, Maxillary first premolar, temporary restoration following endodontic treatmrilt. B, ‘i‘ooth preparation, cusps reduced. cc~nented pins : four’) inserted.
cast restoration with amalgam as a core. since the pins are further from the tooth periphery and thus surrounded by a greater bulk of amalgam.’ Type of pin. A clinical technique for restoring badly mutilated crowns with cemented pins and amalgam was described by Markfey: in 1958. This cemented pin technique uses a 0.025~inch diameter pin cemented in a 0.027-inch pin channel. Markley advocated a circle of pins in a weak root or crown to bind or splint the tooth against splitting.‘, Ii Collard, Caputo, and Standlee’” suggested that pins splint weak teeth and that, in addition to the splinting, masticatory forces are more evenly distributed to the various parts of the tooth, but only when cemented pins are used. Courtade” states, “‘The endodontically treated root is strengthened and splitting of the root is prevented by using five to eight threaded steel rods in the dentin around the root canal filling.”
41
BROWN,
Fig. 1, C and D. C, Restoration finished and polished. D, Facial aspect, completed restoration. Cemented pins show no tendency to cause dentin Self-threading and friction-locked pins defects.” induce stresses that may lead to cracking and crazing of dentin.“‘-‘s These stresses must be avoided to prevent damage to endodontically treated teeth. The cemented pin is the pin of choice for restoring endodontically treated teeth. Advantages of the cemented pin technique include (1) ability to splint roots, (2) resistance and retention form for cavity preparation, and (3) no installation stresses that may induce dentinal damage. Pin channel preparation and pin insertion. Pin channel depth is an important consideration for retention and potential tooth splinting. Research is lacking in resistance to occlusal loading and splinting or reinforcing teeth against splitting as related to pin channel location and depth. Retention of cemented pins is considerably less than that of friction-locked or self-threading pins when they are compared in the laboratory.“’ Markley’ has recommended a depth range of 2 to 5 mm in
42
BARKMEIER,
AND
ANDERSON
Fig. 2, A and 8. A, Mandibular first molar. temporary restoration following endodontic treatment. B, Tooth preparation. cusps reduced, cemented pins (six) inserted. sound dentin for adequate retention of cemented pins. Pin channel depth is dependent on tooth and root morphology, but the upper limits of Markley’s recommendation should provide adequate clinical retention and tooth splinting to protect against tooth fracture. The 0.027-inch pinholes are drilled to a depth of 2 to 5 mm approximately 1 mm from the dentinoenamel junction. A sharp twist drill will prevent lateral cracks in dentin. lb Pin channels should be prepared at slow drill speed, using a single thrust motion and constant air spray to remove debris. The twist drill is aligned by the technique of paralleling the adjacent root surface with the twist drill and then preparing the pinholes with the same orientati0n.l’. 1; Following pin channel preparation a length of 0.025-inch diameter pin* is cut to allow a 2 mm length to be embedded in amalgam when the pin is ‘Star
Dental
Mfg.
Co.. Inc., Conshoshocken,
JANUARY
1979
VOLUME
Pa.
41
NUMBER
1
AMALGAM
RESTORATIONS
OF ENDODONTICALLY
TREATED
TEETH
fully seated in the pin channel. Before cementation, the pin is bent slightly to ensure its coronal portion is well within the body of the amalgam restoration. Zinc phosphate cement is mixed to the consistency required to cement an inlay and is placed in all pinholes with a lentulo spiral and slow-speed contra-angle handpiece. The channel end of the pin is then covered with cement and the pins immediately inserted and allowed to remain undisturbed until the cement has set (Figs. 1, A and B, and 2, A and B). Cavity varnish is not used in the pinholes because the retention of cemented pins is reduced by 46%. I” Utilization
In the final restoration it is always wise to consider and provide for endodontic retreatment. The coronal endodontic filling material is removed to a thickness of approximately 1 mm covering the pulpal floor. A zinc phosphate base of 1 to 2 mm is then placed. In the event endodontic retreatment is necessary, the zinc phosphate base will facilitate gaining access. All surfaces of the cavity preparation are covered with a copal resin varnish. This will seal the margins and prevent marginal microleakage under the amalgam restoration.“‘. ‘I Matrix and amalgam condensation. A matrix band retainer can be used for restoring teeth with minimal coronal destruction. However, for extensive restorations a soldered-band or copper band matrix is required.” “” Following matrix and wedge placement, the amalgam is condensed into the cavity preparation using small condensers to condense the amalgam in the proximity of the pins.“’ After condensation around the pins, large portions of amalgam can be condensed for rapid insertion.“,’ Following condensation, the wedges and matrix are removed and the restoration carved. Occlusal relationships are verified with articulating paper, and the patient is then reappointed for finishing the restoration. Finishing. The finishing appointment has three objectives. These are (1) to verify proximal contours, (2) to ensure occlusal relationships, and (3) to finish and polish the restoration. Radiographic and clinical examinations, to evaluate proximal contour and reveal any overhang of proximal amalgam, are made. The occlusal relationships are again examined and any occlusal discrepancies are corrected. The amalgam alloy restoration is then finished and polished (Figs. 1, C and D, and 2, C). Tarnish and corrosion are reduced by a
THE JOURNAL
of a base and cavity
OF PROSTHETIC
DENTISTRY
varnish.
Fig. 2C. Completed restoration of mandibular molar.
smooth polished surface, and the longevity restoration is thereby increased.”
first
of the
SUMMARY
A technique for restoring endodontically treated posterior teeth has been presented. The pin-amalgam restoration may be used as an acceptable alternative to the cast restoration for situations where a cast restoration is not indicated. REFERENCES ed 1. St. foilis, 1972,Thr 1. W&e. F. S.: EndodonticTherapy. C. \‘. Mosby Co. K. ‘I‘.: 2. Johnson, .J. K.. Schwartz, N. I.., and Blackwell, Evaluation and restoration of endodonticallv treated posterior teeth. J Am Dent Assoc 93:597. 1976. 3. Ingle, J. I.: Endodontics, ed I. Philadelphra. 1965. J.ea CPT Febiger, Publishers. 4. Rosen, H.: Operative procedures on mutilated endodontically treated teeth. .J PROSTHETDew 11:97X 196l. 5. Silverstein, W. H.: The reinforcement of weakened pulpless teeth. J PROSTHETDENT 14:372, liJ64. 6. Dawson, P. E.: Pin-retained amalgam. Dent Clin North Am 14:63, 1971. 7. Markley, M. R.: Pin reinforcement and retrntion of amalgam foundations and restorations. J Am Dent Assoc X:675, 1958. 8. Shillingburg. H. T.. Fisher, D. W., and Dewhirst, K. B.: Restoration of endodontically treated posterior teeth. J PROSTWETDEXT 24:401, 1970. 9. Charbeneau, C. T.: Principles and Practice of Operative Dentistry. Philadelphia, 1975, Lea & Febiger, Publishers. 10. M&a, J. P., Razzano, M. R., and Doyle. M. G.: Pins-A comparison of their retentive properties. LJ .4m Dent ASSOC 78:529, 1969. 11. Bales, D. J,: Operative Dentistry Notebook. \Yilford Hall USAF Medical Center, Lackland .4FB, Texas. .4ugust 1969. 12. Courtade, G. L.: Pin pointers. III. Self-threading pins. J PROSTHET DENT 20:335, 1968. treated 13. Schwartz, N. L.: Restoration of endodontically
43
BROWN,
14.
15.
posterior teeth. Read before the American Prosthodontic Society, Washington D. C., November 1974; Cited br Johnson, .J. K., Schwartz, N. L., and Blackwell, R. T.: Evaluation and restoration of endodontically treated posterior teeth. J Am Dent Assoc 93:597, 1976. Enoch, J. D., and Cochran, M. A.: Pin-retained amalgam. In Baum, I,.: Advanced Restorative Dentistry, Modern Materials and Techniques, ed 1. Philadelphia, 1973, W. B. Saunders Co. Markley, M. R.: Pin retained and reinforced restoration foundations. Dent Clin North Am March 1967, pp 229.
17.
18.
19.
Collard, E. W., Caputo, A. A., and Standlee, J. P.: Rationale for pin-retained amalgam restorations. Dent Clin Sorth Am 14:43, 1970. Courtade, G. I,.: Creating your own “dentin.” Procedures for rebuilding badly broken-down teeth. Dent Clin North Am, Nov. 1963, pp 805-822. Standlee,J. P., Collard, E. W., and Caputo, A. A.: Ijentinal defects caused by some twist drills and retentive pins. J PXOSTHET I)EN.I. 24:18.5, 1970. Moffa, J. P., Razzano, M. R., and Folio, J,: Influence of
20.
21.
22. 23.
INFORMATION
PROSTHE.I.
24.
I>em
35171,
AIVIXRSON
1976.
Phillips, K. W.: Science of Dental phia, 1973, W. H. Saunders Co.
Reprint DR.
AND
cavity varnish on microleakage and retention of variou\ pin-retaining devices. J PXOSTHIX DEXI. 20541, 19611. Going. R. E., and Massler, M.: Influence of cavity liners under amalgam restorations on penetration by radioactive isotopes. J PX0SI.HE.I. DEW 11:298. 1961. Barber, D., Lyell, J.? and Massler, M.: Effectiveness of Copal resin varnish under amalgam restorations. .J P~osru~r Drxr 14533, 1964. Gilmore, 11. W., and Lund, M. K.: Operative Dentistry, ed 2. St. Louis, 1973, The C. V. Mosby Company. Birtcil, R. F., and Venton, E. A.: Extracoronal amalgam restoration utilizing available tooth structure for retention, J
244. 16.
BARKMEIER,
ed 7. Philadel-
requests to:
WAYNE
BOYNE
Materials,
W.
BAKKMEIBR
SCHOOL
OF
DENTAL
PENCE
CREKXTON UNIVERSITY 2500 CALIFORNIA ST. OMAHA,
NEB.
68178
FOR AUTHORS
Most of the provisions of the Copyright Act of 1976 became effective on January 1, 1978. Therefore, all manuscripts must be accompanied by the following written statement, signed by one author: “The undersigned author transfers all copyright ownership of the manuscript (title of article) to The C. V. Mosby Company in the event the work is published. The undersigned author warrants that the article is original, is not under consideration by another journal, and has not been previously published. I sign for and accept responsibility for releasing this material on behalf of any and all co-authors.” Authors will be consulted, when possible, regarding republication of their material.
JANUARY
1979
VOLUME
41
NUMBER
I
