Orthodontic and Orthognathic Treatment Including Transplanted Teeth after Radiotherapy for Rhabdomyosarcoma

Multidisciplinary treatment, which includes chemotherapy, radiotherapy and surgical resection for the head and neck malignant tumor, is often performed in children and adolescents. Although the outcomes of this treatment strategy have been excellent, there are some disadvantages such as growth disturbance in the head and neck region. Since the developing tooth is harmfully affected by chemotherapy and radiotherapy, dental morphological aberration and tooth missing can be induced. One of the reliable treatment options for the missing tooth is auto-tooth transplantation.

Radiotherapy may induce other disadvantages such as dental ankylosis due to periodontium damage. This may raise some occlusion troubles including malocclusion, and rapid bone absorption with progressing periodontitis. Dental ankylosis makes orthodontic treatment difficult due to its immobility. In such a case, a dentoalveolar osteotomy is often performed to move a tooth with the alveolar bone.

We herein report a case of a 14-year-old male who underwent the multidisciplinary treatment for rhabdomyosarcoma of his right cheek when he was 3-year-old. The regimen of chemotherapy was vincristine, actinomycin D, cyclophosphamide and cisplatin according to the Intergroup Rhandomyosarcoma Study-III Protocol. Total radiation dose was 44Gy. He claimed the dental morphological aberration of the permanent teeth at the irradiated region and serious malocclusion. After routine examinations, the following problems were observed: 1) The first molar occlusion relationship was class III at the right and class I at the left. 2) Crowding of teeth at bimaxillary anterior region with discrepancy between the size of the alveolar bone and the width of teeth. 3) Remaining deciduous cuspid of the right upper jaw. 4) Labioclination of the bimaxillary incisors. 5) Short roots of the upper right lateral incisor, canine and premolars and the upper left lateral incisor. 6) Relatively short roots of the upper left central incisor and second premolar and the upper right central incisor.

The deciduous upper right cuspid, and hopeless teeth, lateral incisor, canine and first premolar and upper left lateral incisor were extracted. Simultaneously, the lower first premolars were auto-trasnplanted at the upper right canine and first premolar regions which had been the irradiated site. Root canal fillings of the auto-transplanted teeth were peformed after three weeks and orthodontic treatment was initiated 2 months post-surgery except for the transplanted teeth. Total tooth movement including transplanted was initiated 6 months after the surgery. Subsequently, orthognathic treatment was performed because the right upper central incisor did not move due to dental ankylosis. A dentoalveolar segment including the right upper central incisor was moved en bloc to the best possible position with ideal inclination. Finally, a good occlusion including the transplanted teeth and the moved dentoalveolar segment was created.

Orthodontic treatment including the transplanted tooth after healing can create an ideal dental arch and good occlusion. We consider that best healing term is 6 months after transplantation because of regeneration of the periodontal membrane and the alveolar bone. If dental ankylosis is found, a dentoalveolar osteotomy should be performed to create a good occlusion.

 

1. Gillepsie MB, Marshall DT, Day TA, Mitchell AO, White DR, Barredo JC. Pediatric rhabdomyosarcoma of the head and neck. Curr Treat Opt Oncol 7: 13-22, 2006.

2. Fiorentino G, Vecchinoe P: Multiple congenitally missing teeth: treatment outcome with autologous transplantation and orthodontic space closure. Am J Orthod Dentofacial Orthop 135: 375-379, 2009.