Skeletal relapse following sagittal-split osteotomy for correction of mandibular prognathism.

In a series of 43 cases treated for mandibular prognathism by sagittal-split osteotomy, the change in mandibular position effected by surgery and the degree of relapse 6 months postoperatively were analyzed using lateral cephalograms. In addition, the post-surgical stability of the mandible was compared for prognathism with and without open bite.Overall, the mean changes in vertical and horizontal skeletal parameters were generally small. Post-surgical vertical relapse of prognathism with open bite was larger than that without open bite. Multiple regression analysis did not reveal any association between preoperative morphological pattern and postoperative relapse. Based on these results, the etiology of relapse was discussed.