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A viable alternative: Tooth transplantation
A viable alternative: Sanford
Plainfield,
Tooth transplantation
D.D.S., M.A.*
University of California, School of Dentistry, San Francisco, Calif.
F
rom puberty through adolescence the susceptibility of the human dentition to carious destruction is at its peak, and the most vulernable of these teeth is the mandibular first permanent molar.’ Extensive carious involvement may mean either endodontic treatment or extraction. If extraction is the required treatment, a prosthetic replacement is desirable; but the adolescent patient is not ideal for either fixed or removable prosthodontic treatment. The optimal physiologic stage of development of the donor teeth (third molars) is when the roots are between one-third and one-half formed. This occurs between puberty and the end of adolescence. The purpose of this article is to present a treatment alternative to both removable and fixed prosthetic therapy for patients between 12 and 20 years of age. This age range is the ideal time for autogenous (within the same person) vital tooth transplantation. REVIEW’OF
THE LITERATURE
The dental literature reports many successful autogenous tooth transplantation procedures.2-5 Yet, even though the technique is relatively simple and the reported success rate relatively high (about 95%), it is not a commonly considered treatment alternative for molar replacements in adolescent patients.6 Lefkowitz and Smith’ transplanted tooth buds in rats. In one of their experiments, 36 tooth buds were removed from rat embryos and transplanted into adult rats, both subcutaneously and subperiosteally. Their results suggested t.hat this procedure reduced the host’s graft antagonism. However, they concluded that the present knowledge of histocompatibility indicated that homotransplantation was unsuccessful and that delayed rejection occurs. Apfel’ reported a 95% success rate in autogenous
Presented before the Pacific Coast Society of Prosthodontists, Jasper, Ah,
Canada.
*Clinical Professor, Division of Fixed Prosthodontics, Department of Restorative Dentktry.
THE JOURNAL
OF PROSTHETIC
DENTISTRY
tooth transplantation. This agrees with my findings in over 25 years of performing autogenous transplants. Pafford9 has successfully transplanted homogenous preserved frozen teeth. Homogenous transplants were preserved by placing the teeth in small plastic vials that contained an isotonic saline solution and a small amount of benzalkonium chloride and tetracycline hydrochloride. The containers were placed in a deep freeze maintained at -30” C. The teeth were frozen and stored at this temperature. The two drugs selected were chosen for their antibiotic and germicidal powers and because of the neutral pH. Pafford’ stated that some of the factors remaining to be demonstrated and investigated more satisfactorily are the antigen/antibody phenomenon and the matching of blood types of donor and host. The pulpal tissues of the teeth will not be revascularized if the pulp tissue is agglutinated with the wrong blood type or if hemolysis occurs from an individual antigen/antibody reaction. If the blood types of two persons are not serologically compatible, hemolysis of the introduced erythrocytes takes place almost instantaneously. Pafford’s work was extensive; however, it was a preliminary study. The difficulties encountered regarding host-donor incompatibility and the inadvisability of using medications that inhibit antigenicity point to the impracticability of the general practitioner undertaking any type of homogenous transplantation at this time. Agnew and Fang’* established third molar autogenous transplantation as a feasible and defensible procedure if the roots of the donor teeth were between one-third and one-half formed and trauma to the epithelial root sheaths of the donor teeth could be avoided. GENESIS OF TOOTH
FORMATION
The embryology of the tooth points out the reason why autogenous tooth transplantation is successful. The tooth germ is programmed genetically to complete its formation. It will continue to develop and function in the first or second molar site as long as it is not unduly traumatized surgically.
667
PLAINFIELD
Fig. 1. Tooth germ of a fourth-month human embryo. From Orban, B.J.: Orban’s Histology and Embryology, ed 5. St. Louis, 1962, The C. V. Mosby CO.
Fig. 2. Arrows indicate region of most vulnerable epithelial diaphragm, which must be protected from operative trauma during transplantation procedure. The tooth germ develops from ectoderm and mesoderm. The ectoderm of the oral cavity forms the epithelial enamel organ, which molds the shape of the entire tooth and gives rise to the enamel. The mesoderm differentiates into the dental pulp inside the enamel organ and forms the dentin (Fig. 1). The mesoderm surrounding the enamel organ forms the cementum covering the root and periodontal membrane.”
668
The functional activity of the dental lamina and its chronology may be considered in three phases. The first phase is concerned with the initiation of the entire primary dentition. The second phase deals with the initiation of the successors of the primary teeth. The third phase is preceded by the extension of the dental lamina distally to the tooth germ of the second primary molar. The permanent molars arise directly from the distal extension of the dental lamina. The time of initiation is about 4 months of fetal life for the first permanent molar, the first year for the second permanent molar, and the fourth to fifth year for the third permanent molar. The development of the roots begins after enamel and dentin formation has reached the future cementoenamel junction. The epithelial organ plays an important part in root development. It forms the Hertwig epithelial root sheath, which initiates formation and molds the shape of the roots. Maintaining the integrity of Hertwig’s epithelial root sheath and epithelial diaphragm is absolutely vital in a successful tooth transplantation procedure! Under no circumstances must the epithelial root sheath at the apex of the donor tooth be traumatized (Fig. 2). Thus, during instrumentation in the removal of the donor
NOVEMBER
1983
VOLUME
50
NUMBER
5
TOOTH
TRANSPLANTATION
Fig. 3. A, Preoperative radiograph of acutely abscessedsecond molar. B, Postoperative radiograph 6 months after transplantation of third molar to second molar site. C, Same tooth 1 year postoperatively. D, Same tooth 13 years postoperatively. Tooth tests vital and is asymptomatic.
Fig. 4. A, Preoperative radiograph of chronically abscessed maxillary first molar. B, Postoperative radiograph of transplant after 8 months. C, Same tooth 3 years postoperative1.y. Tooth is asymptomatic.
THE JOURNAL
OF PRDSTHETIC
DENTISTRY
Fig. 5. A, Radiograph of transplant 8 weeks postoperatively. B, Same transplant 6 months postoperatively. C, Same tooth after 4 years. Note atypical root formation. Nevertheless, tooth is asymptomatic and tests vital.
Fig. 6. A, Badly broken-down first molar and tl hird molar in proper developmental stage for transp lant procedure. B, Postoperative radiograph of same tc,oth after 15 years. Transplant tests vital and is asy.mptomatic: 670
tooth, the vulnerable tooth buds are avoided. Furthermore, the host site must be prepared in such a fashion that there is no traumatic impingement on the root buds by bony processes, such as the interseptal bone of the host socket, while the donor tooth is put into position. The precautions that help ensure successful autogenous transplantation are the following: 1. Root development of the donor tooth is between one third and one half of the total root. 2. Hertwig’s epithelial root sheath (epithelial diaphragm) covering the root ends is not injured during surgery. 3. The host site is prepared to avoid injury to the epithelial root sheath when the donor tooth bud is placed in situ. Its preparation should also permit the transplanted tooth bud to remain out of occlusion. 4. The patient should be healthy with a reasonable concern for adequate oral hygiene. 5. Postoperatively, pulpy foods that might pack into the crevicular space during the initial stages of reattachment should be avoided. 6. The patient should consider the procedure important, keep the operative site clean, and protect the transplant from undue trauma until reattachment is complete. One of the most ideal situations for third molar NOVEMBER
1983
VOLUME
50
NUMBER
5
TOOTH
TRANSPLANTATION
transplantation is into the second molar site. The problem of replacing the second molar involves a cumbersome prosthesis. Waiting until the third molar drifts into adequate position may permit the upper second molar to drop out of alignment. Immediately placing the mandibular third molar into the second molar site has been an extremely successful solution to this problem (Fig. 3). When possible, I prefer transplantation to the use of a fixed prosthesis and/or endodontic therapy to restore badly broken-down first molars. A vital tooth is preferable to a devitalized one (Figs. 4 to 6). The autogenously transplanted third molars test vital in approximately ,6 months to 1 year. Patients for whom transplantation procedures are possible are a limited group. The transplant must be in the proper stage of development, which means that the developing tooth must be between one-third and onehalf formed; and the size of the host site must be adequate to receive the transplant. I have performed these procedures on patients between 11 and 19 years of age. This is the time when the caries index is extremely high and the patient’s personal oral hygiene is frequently not acceptable. Patients often change their personal attitude regarding dental care when they see a new virginal implant among the other teeth, many of which contain large amalgam restorai.ions.
procedure and has an extremely high success rate (95%). It is not a treatment that compromises adjacent teeth. It is not an irreversible treatment and does not rule out later prosthetic intervention if necessary.
CONCLUSION
Reprint reyursts to:
Autogenous toolth transplantation is the treatment of choice over fixed or removable prosthodontics in patients between 12 and 20 years of age. It is a simple
DR. SANFORD PLAINFIELD UNIVERSITY OF CALIFORNIA SCHOOL OF DENTISTRY s.4~ FRAN~IXU, CA 94143
THE JOURNAL
OF PROSTHETIC
DENTISTRY
REFERENCES 1.
2.
3.
4.
5. 6. 7. 8. 9. IO. 11.
Plainfield, S.: Twenty-five years of autogenous tooth transplantation. ICD Sci Ed J 10~1, 1977. Rao, C. B., and Dewan, S. K.: Autotransplantation of tooth: Clinical experiences with autotransplantation of developing mandibular third molars to first and second molar sites. J Indian Dent Assoc 46:391, 1974. Bolton, R.: Autogenous transplantation and replantation of teeth: Report on 60 treated patients. Br J Oral Surg 12147, 1974. Joshi, M. R.: Transplantation of third molar. J Dent 1:35, 1976. Kuegelerr, C. J.: Transplantation: A historical review. Ohio Dent J 52~24, 1978. Leffingwell, C. M: Autogenous tooth transplantation: A therapeutic alternative. Dent Surv 56:22, 1980. Lefkowitz, W., and Smith, R. L.: Homotransplantation of tooth buds. IADR Abstr 35~87, 1957. Apfel, H.: Transplantation of the unerupted third molar tooth. Oral Surg 9:96, 1956. Pafford, E. M.: Homogenous transplants of preserved frozen teeth: A preliminary report. Oral Surg 9~55, 1956. Agnew, R. G., and Fong, C. C.: Histologic studies on experimental transplantation of teeth. Oral Surg 9:18, 1956. Orban, B. J.: Orban’s Oral Histology and Embryology, ed 5. St. Louis, 1962, The C. V. Mosby Co.
671
Plainfield,
Tooth transplantation
D.D.S., M.A.*
University of California, School of Dentistry, San Francisco, Calif.
F
rom puberty through adolescence the susceptibility of the human dentition to carious destruction is at its peak, and the most vulernable of these teeth is the mandibular first permanent molar.’ Extensive carious involvement may mean either endodontic treatment or extraction. If extraction is the required treatment, a prosthetic replacement is desirable; but the adolescent patient is not ideal for either fixed or removable prosthodontic treatment. The optimal physiologic stage of development of the donor teeth (third molars) is when the roots are between one-third and one-half formed. This occurs between puberty and the end of adolescence. The purpose of this article is to present a treatment alternative to both removable and fixed prosthetic therapy for patients between 12 and 20 years of age. This age range is the ideal time for autogenous (within the same person) vital tooth transplantation. REVIEW’OF
THE LITERATURE
The dental literature reports many successful autogenous tooth transplantation procedures.2-5 Yet, even though the technique is relatively simple and the reported success rate relatively high (about 95%), it is not a commonly considered treatment alternative for molar replacements in adolescent patients.6 Lefkowitz and Smith’ transplanted tooth buds in rats. In one of their experiments, 36 tooth buds were removed from rat embryos and transplanted into adult rats, both subcutaneously and subperiosteally. Their results suggested t.hat this procedure reduced the host’s graft antagonism. However, they concluded that the present knowledge of histocompatibility indicated that homotransplantation was unsuccessful and that delayed rejection occurs. Apfel’ reported a 95% success rate in autogenous
Presented before the Pacific Coast Society of Prosthodontists, Jasper, Ah,
Canada.
*Clinical Professor, Division of Fixed Prosthodontics, Department of Restorative Dentktry.
THE JOURNAL
OF PROSTHETIC
DENTISTRY
tooth transplantation. This agrees with my findings in over 25 years of performing autogenous transplants. Pafford9 has successfully transplanted homogenous preserved frozen teeth. Homogenous transplants were preserved by placing the teeth in small plastic vials that contained an isotonic saline solution and a small amount of benzalkonium chloride and tetracycline hydrochloride. The containers were placed in a deep freeze maintained at -30” C. The teeth were frozen and stored at this temperature. The two drugs selected were chosen for their antibiotic and germicidal powers and because of the neutral pH. Pafford’ stated that some of the factors remaining to be demonstrated and investigated more satisfactorily are the antigen/antibody phenomenon and the matching of blood types of donor and host. The pulpal tissues of the teeth will not be revascularized if the pulp tissue is agglutinated with the wrong blood type or if hemolysis occurs from an individual antigen/antibody reaction. If the blood types of two persons are not serologically compatible, hemolysis of the introduced erythrocytes takes place almost instantaneously. Pafford’s work was extensive; however, it was a preliminary study. The difficulties encountered regarding host-donor incompatibility and the inadvisability of using medications that inhibit antigenicity point to the impracticability of the general practitioner undertaking any type of homogenous transplantation at this time. Agnew and Fang’* established third molar autogenous transplantation as a feasible and defensible procedure if the roots of the donor teeth were between one-third and one-half formed and trauma to the epithelial root sheaths of the donor teeth could be avoided. GENESIS OF TOOTH
FORMATION
The embryology of the tooth points out the reason why autogenous tooth transplantation is successful. The tooth germ is programmed genetically to complete its formation. It will continue to develop and function in the first or second molar site as long as it is not unduly traumatized surgically.
667
PLAINFIELD
Fig. 1. Tooth germ of a fourth-month human embryo. From Orban, B.J.: Orban’s Histology and Embryology, ed 5. St. Louis, 1962, The C. V. Mosby CO.
Fig. 2. Arrows indicate region of most vulnerable epithelial diaphragm, which must be protected from operative trauma during transplantation procedure. The tooth germ develops from ectoderm and mesoderm. The ectoderm of the oral cavity forms the epithelial enamel organ, which molds the shape of the entire tooth and gives rise to the enamel. The mesoderm differentiates into the dental pulp inside the enamel organ and forms the dentin (Fig. 1). The mesoderm surrounding the enamel organ forms the cementum covering the root and periodontal membrane.”
668
The functional activity of the dental lamina and its chronology may be considered in three phases. The first phase is concerned with the initiation of the entire primary dentition. The second phase deals with the initiation of the successors of the primary teeth. The third phase is preceded by the extension of the dental lamina distally to the tooth germ of the second primary molar. The permanent molars arise directly from the distal extension of the dental lamina. The time of initiation is about 4 months of fetal life for the first permanent molar, the first year for the second permanent molar, and the fourth to fifth year for the third permanent molar. The development of the roots begins after enamel and dentin formation has reached the future cementoenamel junction. The epithelial organ plays an important part in root development. It forms the Hertwig epithelial root sheath, which initiates formation and molds the shape of the roots. Maintaining the integrity of Hertwig’s epithelial root sheath and epithelial diaphragm is absolutely vital in a successful tooth transplantation procedure! Under no circumstances must the epithelial root sheath at the apex of the donor tooth be traumatized (Fig. 2). Thus, during instrumentation in the removal of the donor
NOVEMBER
1983
VOLUME
50
NUMBER
5
TOOTH
TRANSPLANTATION
Fig. 3. A, Preoperative radiograph of acutely abscessedsecond molar. B, Postoperative radiograph 6 months after transplantation of third molar to second molar site. C, Same tooth 1 year postoperatively. D, Same tooth 13 years postoperatively. Tooth tests vital and is asymptomatic.
Fig. 4. A, Preoperative radiograph of chronically abscessed maxillary first molar. B, Postoperative radiograph of transplant after 8 months. C, Same tooth 3 years postoperative1.y. Tooth is asymptomatic.
THE JOURNAL
OF PRDSTHETIC
DENTISTRY
Fig. 5. A, Radiograph of transplant 8 weeks postoperatively. B, Same transplant 6 months postoperatively. C, Same tooth after 4 years. Note atypical root formation. Nevertheless, tooth is asymptomatic and tests vital.
Fig. 6. A, Badly broken-down first molar and tl hird molar in proper developmental stage for transp lant procedure. B, Postoperative radiograph of same tc,oth after 15 years. Transplant tests vital and is asy.mptomatic: 670
tooth, the vulnerable tooth buds are avoided. Furthermore, the host site must be prepared in such a fashion that there is no traumatic impingement on the root buds by bony processes, such as the interseptal bone of the host socket, while the donor tooth is put into position. The precautions that help ensure successful autogenous transplantation are the following: 1. Root development of the donor tooth is between one third and one half of the total root. 2. Hertwig’s epithelial root sheath (epithelial diaphragm) covering the root ends is not injured during surgery. 3. The host site is prepared to avoid injury to the epithelial root sheath when the donor tooth bud is placed in situ. Its preparation should also permit the transplanted tooth bud to remain out of occlusion. 4. The patient should be healthy with a reasonable concern for adequate oral hygiene. 5. Postoperatively, pulpy foods that might pack into the crevicular space during the initial stages of reattachment should be avoided. 6. The patient should consider the procedure important, keep the operative site clean, and protect the transplant from undue trauma until reattachment is complete. One of the most ideal situations for third molar NOVEMBER
1983
VOLUME
50
NUMBER
5
TOOTH
TRANSPLANTATION
transplantation is into the second molar site. The problem of replacing the second molar involves a cumbersome prosthesis. Waiting until the third molar drifts into adequate position may permit the upper second molar to drop out of alignment. Immediately placing the mandibular third molar into the second molar site has been an extremely successful solution to this problem (Fig. 3). When possible, I prefer transplantation to the use of a fixed prosthesis and/or endodontic therapy to restore badly broken-down first molars. A vital tooth is preferable to a devitalized one (Figs. 4 to 6). The autogenously transplanted third molars test vital in approximately ,6 months to 1 year. Patients for whom transplantation procedures are possible are a limited group. The transplant must be in the proper stage of development, which means that the developing tooth must be between one-third and onehalf formed; and the size of the host site must be adequate to receive the transplant. I have performed these procedures on patients between 11 and 19 years of age. This is the time when the caries index is extremely high and the patient’s personal oral hygiene is frequently not acceptable. Patients often change their personal attitude regarding dental care when they see a new virginal implant among the other teeth, many of which contain large amalgam restorai.ions.
procedure and has an extremely high success rate (95%). It is not a treatment that compromises adjacent teeth. It is not an irreversible treatment and does not rule out later prosthetic intervention if necessary.
CONCLUSION
Reprint reyursts to:
Autogenous toolth transplantation is the treatment of choice over fixed or removable prosthodontics in patients between 12 and 20 years of age. It is a simple
DR. SANFORD PLAINFIELD UNIVERSITY OF CALIFORNIA SCHOOL OF DENTISTRY s.4~ FRAN~IXU, CA 94143
THE JOURNAL
OF PROSTHETIC
DENTISTRY
REFERENCES 1.
2.
3.
4.
5. 6. 7. 8. 9. IO. 11.
Plainfield, S.: Twenty-five years of autogenous tooth transplantation. ICD Sci Ed J 10~1, 1977. Rao, C. B., and Dewan, S. K.: Autotransplantation of tooth: Clinical experiences with autotransplantation of developing mandibular third molars to first and second molar sites. J Indian Dent Assoc 46:391, 1974. Bolton, R.: Autogenous transplantation and replantation of teeth: Report on 60 treated patients. Br J Oral Surg 12147, 1974. Joshi, M. R.: Transplantation of third molar. J Dent 1:35, 1976. Kuegelerr, C. J.: Transplantation: A historical review. Ohio Dent J 52~24, 1978. Leffingwell, C. M: Autogenous tooth transplantation: A therapeutic alternative. Dent Surv 56:22, 1980. Lefkowitz, W., and Smith, R. L.: Homotransplantation of tooth buds. IADR Abstr 35~87, 1957. Apfel, H.: Transplantation of the unerupted third molar tooth. Oral Surg 9:96, 1956. Pafford, E. M.: Homogenous transplants of preserved frozen teeth: A preliminary report. Oral Surg 9~55, 1956. Agnew, R. G., and Fong, C. C.: Histologic studies on experimental transplantation of teeth. Oral Surg 9:18, 1956. Orban, B. J.: Orban’s Oral Histology and Embryology, ed 5. St. Louis, 1962, The C. V. Mosby Co.
671