Abstract
The degree of postoperative relapse associated with micrognathia appears much greater than that observed after operation for mandibular prognathism. The inverted-L osteotomy with bone grafting was considered as an alternative method for true lengthening of the mandible and has been advocated to improve postoperative stability compared with other surgical techniques.
The patient was a 18-year 6-month-old female who had mandibular asymmetry and masticatory dysfunction. Computed tomography and panoramic radiograph showed severe deformity of the left ramus and condyle causing micrognathia. After preoperative orthodontic treatment, surgery was performed, including a Le Fort I osteotomy to improve asymmetry of occlusal plane, and advancement of the mandible was accomplished by mandibular sagittal split osteotomy on the right side and the inverted-L osteotomy with interpositioning of a bony autograft on the left side. Furthermore, after a year, onlay graft of the mandible was performed to obtain facial symmetry. The resultant Class I occlusion was apparently stable for a long time. Masticatory function had greatly improved as well as facial esthetics.
