By Francesc Abella, D.D.S., Ph.D., and Miguel Roig, M.D., D.D.S., Ph.D.
Dental autotransplantation entails extracting a tooth from its original site to place it in an edentulous zone, whether it is a post-extraction socket or a surgically prepared socket. (1). This technique was developed as a therapeutic option for teeth loss due to trauma, decay or congenital tooth agenesis, yet fixed dental prostheses and, above all, dental implants, saw its use decline among clinicians.
Decades of problems and complications with implantology have led to reevaluation of tooth preservation and traditional clinical techniques (2). Adverse outcomes associated with implants are largely related to prosthetic (technical) failure and to persistent infections surrounding implants (2, 9, 10). Furthermore, alveolar growth in the anterior maxilla does not stop after pubertal growth peak, but continues throughout the patient’s life. Although this growth is more pronounced in the second and third decade of life, it continues in the fourth and fifth decades. As a result, implant placement in the anterior zone can produce an esthetic compromise due to an implant infraposition caused by progressive growth of the alveolar process in the neighboring teeth and a lack of periodontal ligament (PDL) in the dental implant. This situation is more likely to take place in growing patients, particularly those with a long facial type (3-6). It is recommended therefore to avoid or at least limit dental-implant placement in growing patients, as implants would end up in infraposition (7, 8). Hence, the steady rise in autotransplantations in recent years.
Unlike dental implants, successfully autotransplanted teeth behave identically to natural teeth (11, 12). The presence of PDL allows both the continued formation of bone and soft tissue in the recipient site (13) as well as orthodontic tooth movement (14, 15). Indeed, early orthodontic forces improve prognosis of autotransplanted teeth (16). The main benefits of this technique include enhanced esthetics, dentofacial development, proprioception, and dental arch integrity (17).
Autotransplantation candidates must be carefully selected using clinical and radiographic information. Three-dimensional (3D) cone beam computed tomography (CBCT) radiographic assessment of teeth and their surrounding structures is desirable to plan an autotransplantation procedure (18). Key patient information required consists of anatomic shape, root development of the donor tooth, bone dimension of the recipient socket, as well as compatibility of both the size of the donor tooth and the recipient site. A small field of view CBCT scan not only provides the clinician with a 3D assessment of the area of interest, but also the possibility of segmenting the donor tooth and of manufacturing a 3D-printed tooth replica (19, 20). This step substantially reduces extraoral time, particularly in multirooted teeth where replantation into the socket is challenging.
While successful autotransplantation can yield long-term results, patients should be informed about a possible interruption in the procedure in the event of complications involving the donor tooth extraction and the recipient site (such as insufficient alveolar bone) (21). Frequent complications include inflammatory or replacement resorption, pulp necrosis, lack of healing or compromised healing of the PDL, and a reduction in the final root length (22).
In spite of the large body of research in this area, there is scant scientifically based evidence on autotransplantation due to a lack of randomized controlled clinical trials (RCTs). Careful case selection based on indications can lead to a sufficiently predictable autotransplantation, with survival rates around 90% (22, 23). Besides the extra-alveolar time, other factors that seem to favor a good prognosis include the donor tooth with open apex, good initial primary stability and use of semirigid splinting (21, 24, 25). Regardless of whether donor teeth have an open or closed apex, favorable PDL healing is the key to success (26). Ideal PDL healing occurs when the extracted tooth is replanted in a new site in minimal extraoral time, when most of its cells are still alive (12). PDL cells can be mechanically damaged during extraction or can be affected by changes in pH values, osmotic pressure or dehydration. Atraumatic removal of the donor tooth therefore is critical to successful PDL healing (27).
Most published studies on autotransplantation focus on teeth with immature apices, which might limit the use of this technique to young patients (28-30). Autotransplantation of teeth with open apex, preferably with 2/3 to 3/4 of the root formed, allows root pulp healing and continued root formation. Pulp canal obliteration, a defense response of revascularized pulp, is frequently observed after tooth transplantation procedures (31). Some studies have also reported a high success rate for autotransplantation of mature teeth (11, 32, 33). Since revascularization and pulpal healing are unlikely to occur in closed apex, endodontic treatment is highly recommended to avoid inflammatory root resorption (12, 15). Endodontic treatment can be applied either preoperatively, extraorally during autotransplantation surgery, or within 2 weeks post-surgery (25). In cases with early tooth loss or congenitally teeth agenesis, the recipient site needs to be surgically prepared (34). Satisfactory healing generally appears to take place in autotransplantation in surgically prepared alveolar sockets, since no root resorptions are observed, the PDL space is maintained, and physiological tooth mobility is achieved (33).
To conclude, when the technique is properly and carefully executed in selected cases, autotransplantation is a highly effective procedure. Clinicians must understand the fundamental healing mechanisms of the PDL, the alveolar bone, the gingival tissue, and the pulp. However, there is a need for adequately designed prospective studies with a consensus definition of successful autotransplantation.
- Natiella JR, Armitage JE, Greene GW. The replantation and transplantation of teeth. A review. Oral Surg Oral Med Oral Pathol. 1970;29(3):397-419.
- Giannobile WV, Lang NP. Are dental implants a panacea or should we better strive to save teeth?. J Dent Res. 2016;95(1):5-6.
- Schwartz-Arad D, Bichacho N. Effect of age on single implant submersion rate in the central maxillary incisor region: a long-term retrospective study. Clin Implant Dent Relat Res. 2015;17(3):509-514.
- Aarts BE, Convens J, Bronkhorst EM, Kuijpers-Jagtman AM, Fudalej PS. Cessation of facial growth in subjects with short, average, and long facial types – Implications for the timing of implant placement. J Craniomaxillofac Surg. 2015;43(10):2106-11.
- Daftary F, Mahallati R, Bahat O, Sullivan RM. Lifelong craniofacial growth and the implications for osseointegrated implants. Int J Oral Maxillofac Implants. 2013;28(1):163-169.
- Jemt T, Ahlberg G, Henriksson K, Bondevik O. Tooth movements adjacent to single-implant restorations after more than 15 years of follow-up. Int J Prosthodont. 2007;20(6):626-632.
- Cardona JL, Caldera MM, Vera J. Autotransplantation of a premolar: a long-term follow-up report of a clinical case. J Endod. 2012;38(8):1149–1152.
- Intra JB, Roldi A, Brandao RC, de Araújo Estrela CR, Estrela C. Autogenous premolar transplantation into artificial socket in maxillary lateral incisor site. J Endod. 2014;40(11):1885–1890.
- Albrektsson, T, Donos, N, & Working Group 1. Implant survival and complications. The Third EAO consensus conference 2012. Clin Oral Implants Res. 2012;23 Suppl 6:63–65.
- Pjetursson BE, Karoussis I, Bürgin W, Brägger U, Lang NP. Patients’ satisfaction following implant therapy. A 10 year prospective cohort study. Clin Oral Implants Res. 2005;16(2):185-193.
- Sugai T, Yoshizawa M, Kobayashi T, Ono K, Takagi R, Kitamura N, Okiji T, Saito C. Clinical study on prognostic factors for autotransplantation of teeth with complete root formation. Int J Oral Maxillofac Surg. 2010;39(12):1193-203.
- Tsukiboshi M. Autotransplantation of teeth: requirements for predictable success. Dent Traumatol. 2002;18(4):157-80.
- Park JH, Tai K, Hayashi D. Tooth autotransplantation as a treatment option: a review. J Clin Pediatr Dent. 2010;35(2):129-35.
- Stenvik A, Zachrisson BU. Orthodontic closure and transplantation in the treatment of missing anterior teeth. An overview. Endod Dent Traumatol. 1993;9(2):45-52.
- Tsukiboshi M, Yamauchi N, Tsukiboshi Y. Long-term outcomes of autotransplantation of teeth: a case series. J Endod. 2019;45(12S):S72-S83.
- Kokai S, Kanno Z, Koike S, Uesugi S, Takahashi Y, Ono T, Soma K. (2015) Retrospective study of 100 autotransplanted teeth with complete root formation and subsequent orthodontic treatment. A J Orthod Dentofacial Orthop. 2015; 148 (6), 982-989.
- Kim MS, Lee HS, Nam OH, Choi SC. Autotransplantation: a reliable treatment modality for severely malpositioned teeth. J Clin Pediatr Dent. 2017;41(5):388-391.
- Anssari Moin D, Verweij JP, Waars H, van Merkesteyn R, Wismeijer D. Accuracy of computer-assisted template-guided autotransplantation of teeth with custom three-dimensional designed/printed surgical tooling: a cadaveric study. J Oral Maxillofac Surg. 2017;75(5):925.e1-925.e7.
- Verweij JP, van Westerveld KJH, Anssari Moin D, Mensink G, van Merkesteyn JPR. Autotransplantation with a 3-dimensionally printed replica of the donor tooth minimizes extra-alveolar time and intraoperative fitting attempts: a multicenter prospective study of 100 transplanted teeth. J Oral Maxillofac Surg. 2020;78(1):35-43.
- Ashkenazi M, Shashua D, Kegen S, Nuni E, Duggal M, Shuster A. Computerized three-dimensional design for accurate orienting and dimensioning artificial dental socket for tooth autotransplantation. Quintessence Int. 2018;49(8):663-671.
- Almpani K, Papageorgiou SN, Papadopoulos MA. Autotransplantation of teeth in humans: a systematic review and meta-analysis. Clin Oral Investig. 2015;19(6):1157-79.
- Rohof ECM, Kerdijk W, Jansma J, Livas C, Ren Y. Autotransplantation of teeth with incomplete root formation: a systematic review and meta-analysis. Clin Oral Investig. 2018;22(4):1613-1624.
- Chung WC, Tu YK, Lin YH, Lu HK. Outcomes of autotransplanted teeth with complete root formation: a systematic review and meta-analysis. J Clin Periodontol. 2014;41(4):412-23.
- Kafourou V, Tong HJ, Day P, Houghton N, Spencer RJ, Duggal M. Outcomes and prognostic factors that influence the success of tooth autotransplantation in children and adolescents. Dent Traumatol. 2017;33(5):393-399.
- Jang Y, Choi YJ, Lee SJ, Roh BD, Park SH, Kim E. Prognostic factors for clinical outcomes in autotransplantation of teeth with complete root formation: survival analysis for up to 12 years. J Endod. 2016;42(2):198-205.
- Andreasen JO, Paulsen HU, Yu Z, Ahlquist R, Bayer T, Schwartz O. A long-term study of 370 autotransplanted premolars. Part I. Surgical procedures and standardized techniques for monitoring healing. Eur J Orthod. 1990;12(1):3-13.
- Andreasen JO. Effect of extra-alveolar period and storage media upon periodontal and pulpal healing after replantation of mature permanent incisors in monkeys. Int J Oral Surg. 1981;10(1):43–53.
- Strbac GD, Giannis K, Mittlböck M, Fuerst G, Zechner W, Stavropoulos A, Ulm C. Survival rate of autotransplanted teeth after 5 years – A retrospective cohort study. J Craniomaxillofac Surg. 2017;45(8):1143-1149.
- Mertens B, Boukari A, Tenenbaum H. Long-term follow up of post-surgical tooth autotransplantation: a retrospective study. J Investig Clin Dent. 2016;7(2);207-214.
- Lundberg T, Isaksson S. A clinical follow-up study of 278 autotransplanted teeth. Br J Oral Maxillofac Surg. 1996;34(2):181-185.
- Siers ML, Willemsen WL, Gulabivala K. Monitoring pulp vitality after transplantation of teeth with mature roots: a case report. Int Endod J. 2002;35(3):289-294.
- Bae JH, Choi YH, Cho BH, Kim YG, Kim SG. Autotransplantation of teeth with complete root formation: a case series. J Endod. 2010;36(8):1422–1426.
- Yu HJ, Jia P, Lv Z, Qiu LX. Autotransplantation of third molars with completely formed roots into surgically created sockets and fresh extraction sockets: a 10-year comparative study. Int J Oral Maxillofac Surg. 2017;46(4):531-538.
- Bauss O, Zonios I, Rahman A. Root development of immature third molars transplanted to surgically created sockets. J Oral Maxillofac Surg. 2008 66(6):1200-1211.