Shengjiaxin operation is a long arc operation of mandibular angle, which is safe and effective. The shape of chin has distinct personality characteristics, the man is resolute and the woman is handsome. Westerners attach great importance to the shape and size of chin in appearance aesthetics, but in China, the role of chin and its value in face aesthetics are often ignored. If the face is compared to a beautiful article, then the chin is like a wonderful pen that makes the finishing point. Nice symmetrical chin, good ending. Even if the facial features are flat, the smooth and balanced outline lines will give people a clear and pleasing feeling.