Analysis of relapse after mandibular advancement surgery.

Seventeen cases of mandibular advancement surgery were evaluated for skeletal relapse; 12 included long-term evaluation. Inferior movement of the proximal segment with displacement of the condyle occurred at the time of surgery or in the immediate postoperative period. This movement was closely associated with subsequent skeletal relapse of the distal segment. This may represent a cause-and-effect relationship mediated through the soft tissue attachments of periosteum and muscle that are stretched at the time of surgery.