Poster 134: Mandibular Advancement With Distraction Osteogenesis for Adult Class II Malocclusion Patients With Condylar Resorption

Abstract

Distraction osteogenesis has a favorable effect on TMJ and is beneficial for prevention of relapses after mandibular advancement in Class II malocclusion patients. Here we report on mandibular advancement in patients with preoperative condylar resorption who require more than expected advancement and review the medical literature. Distraction osteogenesis using an intraoral device was performed in five patients with mandibular hypoplasia. All patients were adults over the age of 18. All patients had condylar bone resorption preoperatively. The distraction was performed intraorally with a modified SSRO. After seven days of a latency period, activation was performed at the rate of 1.0 mm/day with two turns.. The devices were removed after a 4-8 month consolidation period. n/a Total advancement of the mandible was an average of 13 mm. Cephalometric comparisons from immediately after the removal of the device to six months later revealed an average 3.4 mm relapse. Therefore, mandibular advancement with distraction osteogenesis requires overcorrection and elastic rehabilitation after adequate consolidation periods. Greater mandibular advancement can be achieved with distraction osteogenesis in patients with severe mandibular hypoplasia with condylar resorption. However, relapses were found during follow-up and therefore over correction appears to be needed for improved results. Further evaluation of distraction osteogenesis with long-term follow-up is needed.