The Study Of Profile Changes After Bilateral Sagittal Split Ramus Osteotomy

objective:The aims of this retrospective cephalometric study were to estimate the changes of soft tissue profile of mandibular protrusion patients after bilateral sagittal split ramus osteotomy. Compare the measurement items with the database of people with normal occlusion, and estimate the soft tissue profiles post-orthognathic surgery.Method:Fifteen patients with mandibular protrusion underwent bilateral sagittal split ramus osteotomy were retrospectively reviewed, in the department of oral and maxillofacial surgery,2nd affiliated hospital, medical school of Zhejiang University from2003to2011. All patients did cephalometric before the operation, made night guard by model surgery, performed the bilateral sagittal split ramus osteotomy. Lateral cephalograms with the teeth in habitual occlusion were taken before and approximately six months after surgery. A cephalometric appraisal was used to study24measurement items. Paired t-test and independent samples t-test analysis were used to evaluate the changes in soft tissue of facial profile.Results:1.16out of24measurement items were different significantly before and after the surgery in all patients.2. These measurement items were compared with the database of people with normal occlusion. There were statistics difference in2measurement items. Conclusions:Treatment of Class Ⅲ malocclusion frequently requires a combination of orthodontics and orthognathic surgical procedures. Bilateral sagittal split ramus osteotomy can correct the mandibular protrusion by setting back the mandible adequately. However, the post—surgery parameters still indicated a mild prognathism compared with the normal.