Osteotomies in Orthognathic Surgery

Orthognathic surgery is mostly performed to correct developmental or acquired oral and maxillofacial skeletal deformities (OMSDs). During the past three decades, significant advances in surgical osteotomy techniques and instrumentation have been developed and carried out in orthognathic surgery. However, the basic surgical principles have more or less remained unchanged. At the same time, numerous surgical techniques have been developed and refined and used by surgeons in the field of oral and maxillofacial surgery. These techniques have treatment of the most complex dentofacial deformities with confidence. Additionally, it has been possible to predict the results of the treatment. Although the initial surgical techniques for correction of anterior mandibular open bite were reported as early as the late 1800s, widespread use of currently acceptable techniques began in the middle of the last century. Detailed surgical planning is essential for a successful outcome. The treatment involves an accurate treatment plan, correct type of instruments for a specific procedure, a thorough surgical routine, and adherence to the guidelines for each routine. Although similar orthognathic surgical techniques are used, there are multiple important differences related to each osteotomy. It is essential for the surgeon to understand these differen‐ ces in order to provide an effective and safe surgical care for the patient with facial anomalies. Choosing an optimal method of osteotomy depends on many factors, including the indication for treatment, the goal of therapy, patient profile, underlying medical conditions, and the magnitude of surgical movement. The major objective of this chapter is to provide practical guidelines and principles of osteotomies and commonly used techniques. These guidelines are based on a review of the current literature and the author's personal experience. The chapter focuses on the history of orthognathic surgery, anatomical considerations, indications for different osteoto‐ mies, and the surgical technique for each osteotomy. Techniques such as the Le Fort I, II, III osteotomies, segmental osteotomies of the maxilla, bilateral sagittal split osteotomy (BSSO), bilateral vertical osteotomy (BVO) genioplasty, segmental osteoto‐ my of the mandible, and the chin wing osteotomy are described.