There are many methods, and it is necessary to choose the appropriate surgical method according to different situations. Such as high cheekbone reduction surgery, mandibular angle hypertrophy surgery (square face becomes oval face), chin horizontal osteotomy forward surgery (correction of small chin) and so on. With the increasingly sophisticated surgical instruments, people's experience is gradually enriched. The above three kinds of commonly used face-changing operations can be completed only through the incision in the mouth, which greatly reduces the risk of surgery and the effect of surgery is getting better and better.