Results after mandibular advancement surgery: an analysis of 87 cases.

Clinical results and stability after mandibular advancement surgery were evaluated in a multi-institutional study of 87 individuals. Skeletal and dental stability were evaluated by a computer morphometric technique and clinical results were determined by recall of patients. Analyses of multiple variables were performed to determine factors that contributed to optimum treatment results or relapse, or both, after mandibular advancement. It was found that the mandible can be advanced successfully in all types of mandibular deficiency. Problems primarily related to surgical technique, such as postoperative condylar distraction, were consistently associated with relapse. Position of the proximal segment and the use of skeletal fixation were important in preventing relapse, but the value of suprahyoid myotomies and cervical collars was not proved. Significant postural changes of the head and cervical spine were observed after surgery.