Your condition is called mandibular angle hypertrophy, which can be either skeletal hypertrophy or masseter hypertrophy. In either case, it can be corrected by plastic surgery. This operation is performed under local anesthesia or general anesthesia, and the incision can be in the mouth or in the skin. The doctor will discuss the decision with you. Smooth the mandible and remove part of the masseter muscle. Usually you can go to work in three or four days. The swelling after this operation is serious, and the effect often appears within one to three months after the operation.