A Case of Mandibular Prognathism with Narrow Maxilla Treated by Surgically Assisted Rapid Palatal Expansion （SARPE） and Two-jaw Osteotomy

In patients with severe mandibular prognathism, maxillary deficiency is commonly seen. We report the successful surgical orthodontic treatment of a patient with severe mandibular prognathism and narrow maxilla. A male aged 26 years and 8 months with a chief complaint of anterior crossbite was diagnosed with severe skeletal Class Ⅲ and Angle Class Ⅲ malocclusion with a narrow maxilla. We aligned the lower dental arch, followed by surgically assisted rapid palatal expansion （SARPE） for the maxilla using two distractors placed on premolars and molars to expand the posterior area more widely than the anterior area of the maxillary dental arch; as a result, the arch form of the maxilla was well corrected and coordinated with the mandible. Following maxillary advancement and impaction by Le Fort Ⅰ osteotomy and mandibular set-back, sagittal split ramus osteotomy （SSRO） improved the patient’s occlusion and facial profile. The resultant occlusion and satisfactory facial profile were maintained during the 2-year retention period.