Munster Leo, an internationally renowned plastic surgeon, said, "It is not only fair and smooth skin but also the perfect facial contour that determines a beautiful appearance.". Facial contour is a person's "first business card". Even if a person's personality is kind and gentle, if her face is angular, many people will think that this person should not be easy to get along with. The outline of a person's face largely determines others' first impression of that person. When strangers meet for the first time, they usually simply use "good" or "bad" to distinguish the first impression. At this time, the first impression is not the judgment of a certain part of a person's face, but the impression of the whole outline, that is, the face shape. Whether the face looks good or not plays a vital role in the mandibular angle. The mandibular angle is located on the lower lateral side of the face and constitutes the main frame structure of the 1/3 contour under the face. Its position and shape have obvious gender signs, and the hypertrophy of mandibular angle makes people feel masculine, so men take square face as beauty, while oriental women take oval face as beauty. Orientals and westerners have completely different aesthetic views on women's faces. Oriental women want their facial contours to be oval, just like The Story Of Diu Sim, Yang Guifei and Wang Zhaojun. Oriental aesthetics holds that the oval face represents the charm, beauty, quietness, gentleness and kindness of women. The square face of women makes people feel not gentle and lacks feminine charm. Careful observation of the expected imitators will reveal that most of them not only have beautiful eyes and noses, but also have an egg-shaped facial contour. The square face can be changed by narrowing the mandibular angle. This kind of surgery mainly changes the exoskeleton by grinding or cutting, which is the most important means to change the facial contour. Because cosmetic surgery requires no trace, oral mucosal incision is now used, and a soft and delicate face can be created in about 2 hours by using a micro-pendulum saw dedicated to maxillofacial surgery.