Autotransplantation for a Missing Permanent Maxillary Incisor

Resident: Jason Hencler
Date: 09/04/2009

Article title: Case Report:
Autotransplantation for a Missing Permanent Maxillary Incisor

Author(s): Rao DDS, MS; Fields DDS, MS, MSD; Chacon DDS, MS
Journal: Pediatric Dentistry V30/NO 2 2008

Major topic: Autotransplantation as treatment option

Type of Article: Case Report

Main Purpose:
To describe the treatment of loss of a permanent incisor using transplantation of a maxillary first premolar to the incisor position.
Current Treatment Modalities: Dentists have multiple options to treat missing permanent maxillary anterior teeth that are lost during the mixed dentition due to trauma, decay, or developmental factors. These options include FPD, RPD, implants, ortho space closure, and autotransplanted permanent teeth.

Case Description:
9yo female presents with a chief complaint of unerupted tooth #9. Radiographs revealed an ectopically erupting (inverted) #9 with delayed root development. Tx options included EXT followed by either: prosthetics, asymmetric ortho space closure, surgical uncovering followed by ortho repositioning, or autotransplantation of the inverted tooth to a more acceptable position followed by ortho repositioning.

Treatment:
Autotransplantation with ortho traction to reposition inverted #9 was selected as initial tx. #9 was surgically exposed and revealed a significant dilacerations of the root. Due to future problems of moving such a tooth, decision was made to EXT. Revised tx plan was autotransplantation of maxillary 1st PM. After the site was surgically prepared, the PM was EXT and transplanted with its mesial surface facing buccal. The site was allowed to heal for 2 mos. Eval at 8 wks demonstrated grade II mobility. The labial and lingual surfaces were reduced incrementally to avoid pulp irritation. The implanted tooth was extruded while the adjacent teeth were intruded.

Key points in the article discussion:
Most traumatic injuries to permanent incisors occur in the mixed dentition, which is when PM roots are developing. Since partial root formation (2/3-3/4) is one of the requirements for god prognosis, PMs are likely donors for autotransplantation of incisor sites. At ½ root formation there is an 80% chance of optimal root length and over 90% chance of pulpal and perio healing. The presence of open apices seems to be crucial for good prognosis. Recipient site bone area should be 1-2mm wider and deeper than the dimension of the donor root. Some authors recommend porcelain laminate veneers over composite build up for best esthetics. If the transplant fails, which is rare, final treatment with an implant can still be accomplished if the alveolar bone support was maintained. No definitive data has been reported for ideal post op stabilization period for transplanted teeth. Initial perio healing around a transplanted tooth takes about 4 wks and complete perio healing can be observed radiographically around 8 wks. Because pulpal necrosis and inflammatory resorption are noticed usually w/in 2 mos post surgery, a waiting period of at least 12 wks is best before applying ortho forces. Generally antibiotics are not required but anti plaque rinses are often used during healin periods. Ortho tx can be initiated w/in 3-4 mos of the transplantation. This allows for adequate perio healing prior to complete pulpal obliteration, thus preventing late pulpal necrosis. Light, continuous ortho forces are best.

Summary of conclusions:
With its high success rate and by following reliable techniques, autotransplantation of a permanent maxillary central incisor with a maxillary PM is a favorable option that should be considered.

Assessment of article:
This article was very interesting. Although autotransplantation is not a very popular in the USA, it should be considered in situations similar to the case presented in this article. As a pediatric dentist, we would undoubtedly see such cases. A multi disciplinary approach, working with other specialists should definitely be taken when considering autotransplantation.