上下歯列弓幅径の不調和を伴う骨格性下顎前突症の１例―上顎２分割Ｌｅ Ｆｏｒｔ Ｉ型骨切り術と下顎枝垂直骨切り術の併用による咬合改善―

Abstract

This case report presents the surgical orthodontic treatment with two-piece maxillary Le Fort I and intraoral vertical ramus osteotomies of the mandible (IVRO). The patient was a 21-year 3-month-old female with the chief complaint of reversed occlusion and temporomandibular joint pain. The patient had mandibular prognathism with an overbite of 3 mm and overjet of −4 mm and Class III canine and molar relationships. Cephalometric analysis showed a skeletal Class III relationship (ANB, −2.5 degrees). The presurgical orthodontic treatment started with a multi-bracket appliance and without premolar extraction. An arch-width discrepancy between the maxilla and mandible was observed in the dentoalveolar region, which was compensated by buccal inclination of the maxillary posterior teeth and lingual inclination of the mandibular posterior teeth. After 20 months of presurgical orthodontic treatment, a 2-jaw surgery including two-piece maxillary Le Fort I and IVRO was performed. The total treatment period was 28 months. A good facial profile and occlusal relationship were obtained. Our results suggested that orthodontic treatment incorporating two-piece maxillary Le Fort I and IVRO might be effective for patients with arch-width discrepancy between the maxilla and mandible.