Bone-cutting and face-lifting is a minimally invasive operation, so the operation will not leave scars. Bone-cutting and face-lifting is mainly to restore the normal shape of the mandibular angle by removing the part that is too prominent, so that the face becomes a beautiful oval or oval face. Mandibular angle resection requires precise surgical instruments, and the surgeon must have the artistic aesthetics and first-class surgical techniques like a sculptor. Traditional mandibular angle osteotomy includes intraoral incision and extraoral incision. Micro pendulum saw, chisel or rongeur were used to remove the coarse mandibular angle during the operation. These methods all have their scope of application, advantages and disadvantages. For example, the incision of oral incision method is relatively hidden, and there are no surgical traces on the face, but fewer bones are removed. Generally speaking, there is no trace.