多分割 Le Fort I 型骨切り術を併用した上下顎移動術 −ガミースマイルと上顎歯列狭窄を伴った上顎前突および下顎後退症への応用−

Abstract

A 21-year-old woman presented with maxillary protrusion and a gummy smile along with mandibular retrognathism. Moreover, an arch width discrepancy was observed between the maxilla and the mandible. After 10 months of presurgical orthodontic treatment using a multibracket appliance, multi-segment Le Fort I osteotomy and sagittal split ramus osteotomy were performed. In the maxilla, the upper first premolars were extracted, and subsequently the upper arch was divided with a piezoelectric device into 4 segments after a down fracture. The anterior maxillary segment was moved distally to close the space, and the posterior maxillary segments were moved laterally to correct the excessively narrow maxilla. After 3 months of postsurgical orthodontic treatment, a favorable facial profile and occlusal relationship were obtained. The total treatment period was 13 months. A multi-segment Le Fort I osteotomy greatly contributed to shortening the duration of therapy for arch width discrepancy between the maxilla and the mandible. These results suggest that piezosurgery might be effective and safe for multi-segment Le Fort I osteotomy.