The chin, commonly known as the “chin”, is composed of the connection of the horizontal part of the bilateral mandibles and is an important part of the lower third of the face, and its own morphological position and coordinated proportional relationship with the upper and middle face are important factors in facial aesthetics. Underdevelopment of the chin can be manifested as “pointed mouth” deformity, while overdevelopment of the chin can cause “long face” or “horse face” deformity, in addition to underdevelopment and overdevelopment, deviation of the chin can also In addition to underdevelopment and overdevelopment, chin deviation can also cause asymmetry of the entire face and affect the aesthetics of the patient. Severe chin recession deformity can also cause sleep apnea syndrome, which can lead to complications such as hypertension, coronary heart disease, diabetes and cerebrovascular disease and traffic accidents, and even sudden death at night. Chin osteotomy is an ideal treatment for chin dysplasia, which improves the chin profile while correcting double chin, relieving upper airway pressure to improve ventilation, and treating sleep apnea syndrome at the same time. The incision line is designed in the mucous membrane on the labial side of the mandibular gingival-buccal groove, the mucous membrane is cut open to reach the surface of the chin bone, the periostealer is stripped to reveal the anterior edge of the chin bone, the scope of stripping is appropriate to meet the designed osteotomy line, as much as possible to preserve the soft tissue attachment of the chin to ensure the blood supply of the osteotomy block, the median chin line and the horizontal osteotomy line are marked with a small grinding ball, the horizontal osteotomy line is located below the bilateral chin holes and parallel to the jaw plane, about 1 cm from the lower edge of the chin. The horizontal osteotomy line is located below the bilateral chin holes and parallel to the jaw plane, about 1cm from the lower chin margin, and is used to complete the osteotomy along the osteotomy line with a resurfacing saw. The common osteotomy methods are: 1. horizontal forward shift: the most commonly used osteotomy method in chinplasty, applicable to patients with simple chin recession, patients with serious chin recession can use chin stepped osteotomy forward shift; 2. forward shift extension: applicable to patients with chin recession accompanied by short chin bone development in the vertical direction, a method commonly used in clinical correction of small chin deformity; 3. horizontal left and right shift: applicable to patients with normal chin height and 3.Horizontal shift rotation: if the chin is skewed and the bilateral chin nodes are basically symmetrical and located at the same level, it can correct the horizontal skewed chin deformity; 4.Horizontal shift rotation: if the chin is skewed and the bilateral chin nodes are located at the same level but the front and back direction is not the same, when moving from side to side, it can do front and back and up and down rotation at the same time; 5.Shortening forward or backward: it is suitable for patients with chin recession or protrusion, and at the same time accompanied by vertical overgrowth; 6.Chin chevron bone excision: it is a common clinical method to correct chin deformity. The chin is not only a small bone, but also a small bone, which can be removed in the middle of the chin while completing the horizontal osteotomy of the chin.