Criteria and limitations for selecting a sagittal split ramus osteotomy for patients with skeletal mandibular prognathism and open bite

The purpose of this study is to elucidate the criteria and limitations for selecting a sagittal split ramus osteotomy (SSRO) alone for patients with skeletal mandibular prognathism and open bite.The relationship between the mandibular relapse after 1 year and the extent of vertical movement following SSRO alone was investigated for patients with skeletal mandibular prognathism and open bite and the criteria were determined.The limitation in SSRO alone was found to be 3-mm vertical movement at the gonion. There was a significant difference in the mandibular relapse between the patients with3-mm change and3-mm change.For patients with skeletal mandibular prognathism and open bite, if the vertical movement at the gonion is3 mm, SSRO alone could be an effective treatment. However, if the movement is3 mm, SSRO alone should be avoided and bimaxillary osteotomies may be a preferable treatment.