Stability of the mandible after sagittal ramus osteotomy for correction of prognathism.

The change in the position of the mandible after sagittal ramus osteotomy was evaluated on lateral cephalograms and in dental casts in 44 patients with mandibular prognathism. The postoperative relapse of the mandible at four landmarks was less than 1 mm on cephalograms and 1.1 mm at the first molar on the side with the larger posterior movement. The tendency to relapse was greater in cases in which large posterior and/or lateral movements of the mandible occurred at surgery. The importance of proper postoperative care and avoidance of lateral shift of the mandible to minimize relapse is stressed.