Restoration of an alveolar bone defect caused by an ankylosed mandibular molar by root movement of the adjacent tooth with miniscrew implants.

Ankylosis of a tooth is a pathologic condition commonly manifested by infraocclusion and vertical alveolar bone defect of the involved tooth. Extraction is often indicated in patients with severe tipping of adjacent teeth and serious infraocclusion, rather than attempting orthodontic repositioning. However, the residual alveolar bone defect after extraction must be restored adequately to establish sound dentition with a healthy periodontium. The bone-forming potential of sound periodontal ligament cells of the adjacent teeth can be used to restore the bone defect, through precisely controlled mesial movement of the root of the tilted molar. In this case report, a successful mesial root movement of the mandibular second molar is shown by the combined use of a conventional uprighting spring and orthodontic miniscrew implants in the mandibular premolar area. Adequate occlusion and periodontal health were restored in a 15-year-old girl with the typical sequela of an ankylosed molar.