Moving an ankylosed central incisor using orthodontics, surgery and distraction osteogenesis

When a dentist replants an avulsed tooth, the repair process sometimes resu lts in the cementum. of the root and the alveolar bone fusing together, wit h the replanted tooth becoming ankylosed. When this occurs, the usual proce ss of tooth movement with bone deposition and bone resorption at the period ontium cannot function. If dental ankylosis occurs in the maxillary incisor of a growing child, the ankylosed tooth also cannot move vertically with t he subsequent vertical growth of the alveolar process. This results in the ankylosed tooth leaving the plane of occlusion and often becoming esthetica lly objectionable. This report describes a 12-year-old female with a centra l incisor that was replanted 5 years earlier, became ankylosed, and left th e occlusal plane following subsequent normal vertical growth of the alveola r process. When growth was judged near completion, the tooth was moved back to the occlusal plane using a combination of orthodontics, surgical block ostectomy, and distraction osteogenesis to reposition the tooth at the prop er vertical position in the arch. This approach had the advantage of bringi ng both the incisal edge and the gingival margin of the clinical crown to t he proper height in the arch relative to their antimeres. Previous treatmen t procedures for ankylosed teeth have often involved the extraction of the affected tooth. When this is done, a vertical defect in the alveolar proces s results that often requires additional bone surgery to reconstruct the ve rtical height of the alveolar process. If the tooth is then replaced, the r eplacement tooth must reach from the final occlusal plane to the deficient ridge. This results in an excessively long clinical crown with a gingival h eight that does not match the adjacent teeth.