正颌外科是应用外科手术和口腔正畸学的方法联合矫治牙颌面畸形，使病人容貌美观，牙齿排列整齐。由于遗传或发育的原因，有些青少年出现面颌骨三维空间结构比例失调，形成各种牙颌面的畸形，这不仅影响患者的咀嚼功能，而且容貌畸形还给患者带来精神上的痛苦［１，２］。因此 Orthognathic surgery is the application of surgery and orthodontics orthodontics joint correction of dental and maxillofacial deformities, the patient looks beautiful, the teeth arranged in neat rows. Due to genetic or developmental reasons, some adolescents appear facial mandible three-dimensional spatial structure imbalance, the formation of a variety of dental and maxillofacial deformities, which not only affect the patient’s masticatory function, but also to patients with facial deformity mental pain [1 , 2]. therefore