Medial pterygoid muscle and stylomandibular ligament: the effects on postoperative stability.

The postoperative skeletal stability following surgical advancement of the mandible can be influenced by several factors. The effect of the medial pterygoid muscle and the stylomandibular ligament on the stability of results following surgical advancement has possibly been underestimated. In this retrospective study, the long-term postoperative skeletal stability following surgical advancement of the mandible in two groups of patients was studied and compared. In one group the medial pterygoid muscle and the stylomandibular ligament were stripped from the medial side of the angle of the mandible during the bilateral sagittal split osteotomy (BSSO) procedure while for the other group of patients these muscles and ligaments were left attached. The long term skeletal stability of the two groups was compared and the group that had the muscles and the ligaments stripped proved to be more stable than the other group.