A patient with a large, squarish, or broad face who desires a small, round, or slender face can undergo mandibular contouring surgery to reduce the width of the lower face. The successful correction of a prominent mandibular angle by conventional angle ostectomy has been reported. However, in the majority of patients with a widened facial appearance, both the mandibular angle and part of the mandibular body anterior to it are protuberant laterally, so both must be resected. At our clinic, operations to reduce the width of the lower face have been performed on 76 patients (9 males and 67 females) during the last 5 years. Initially, we employed a combination of shaving of the lateral cortex and multistaged curved cuts of the mandibular angle. This operative technique, however, required a high level of skill and was time-consuming. A retrospective study of the results revealed the following additional drawbacks. The objective of this procedure is, in a sense, to create morphologically analogous mandibles in all patients, but on the one hand, the resulting relief of the mandibular angle tended to lack individuality, and on the other hand, the primary purpose of reducing the width of the lower face was not fully accomplished in some patients. With angle-splitting ostectomy, which we performed at a later date, however, the width of the lower face was efficiently reduced, producing a natural relief of the mandibular angle. If the surgeon in charge has precise anatomic knowledge and performs this on the basis of an accurate preoperative diagnosis and an operative plan, he or she will encounter no particular difficulties during the operation. There were no complications, such as hematoma, infection, or asymmetry, and aesthetic benefits were achieved even in patients with facial asymmetry.
