Anterior tooth anticollision (Class III malocclusion), which is often referred to as “geoblast”, has a high prevalence of 4-14% in Asian populations, while the prevalence rate of 12.81% was found in the results of an epidemiologic survey of adolescents in 2002 in China, which is already quite high. Class III malocclusion is broadly categorized into three groups according to structure, etiology and prognosis: odontogenic: functional and osseous. Odontogenic: due to obstacles in the process of tooth eruption and replacement, the mandibular molar teeth move proximally and centrally, resulting in a Class III molar relationship, some of which is accompanied by anterior anticlocking. Usually, the size, shape and position of maxillary and mandibular jaws are basically normal in odontogenic Class III malocclusion, which is relatively simple to correct and has a good prognosis. Functional: Also known as muscular, any acquired, neuromuscular involvement, mandibular forward displacement of the formation of Ann’s class III malocclusion is called functional class III malocclusion or pseudo class III malocclusion. Occlusal interference and early contact are the main causes of functional mandibular protrusion. Usually, the size, shape, and position of the maxilla and mandible are basically normal in functional Class III malocclusion, which results in a better response to treatment and a better prognosis. Bone: Abnormal jaw relationship due to unbalanced growth of maxilla and mandible, manifested by overdevelopment of mandible and underdevelopment of maxilla, proximal and middle molar relationship, anterior teeth anticollision, significant Class III facial shape, and inability of the mandible to recede to the opposite edge. Bony Class III malocclusion is also known as true Class III malocclusion, and serious cases need to cooperate with surgery. Of course, if parents find that their children have “parietal”, it is best to go to the orthodontic department of the local dental hospital to find an orthodontist for examination and diagnosis if possible. Generally speaking, 65% belongs to mild, through simple orthodontic treatment can be solved; 20% belongs to moderate, 10% belongs to severe, the above 30% still need to have the technology of orthodontist to solve; only 5% particularly serious, non-surgical can not be solved. However, bony Class III malocclusion is a developmental deformity that worsens with age. It is also difficult for doctors to determine the future development of the jaw when the anterior teeth are inverted in early childhood. When a child is found to be “circumcised”, the parents will be very worried and hope that the child can be treated and cured as soon as possible. The doctor understands the parents’ feelings, but there are some principles of treatment: we cannot say that the earlier the better, but my principle is to intervene in the most cost-effective period of time for early orthodontic treatment, and to choose high-efficiency orthodontic appliances in the shortest possible orthodontic treatment course. I usually choose to wait a little bit during the period of milk teeth, some of the mild ones can be solved by themselves when replacing the teeth, and even if the milk teeth are solved in the middle and severe ones, the anastomosis will still remain after replacing the permanent teeth. In the early mixed dentition period, we will intervene after the eruption of 2 or 4 incisors in the upper jaw. Generally, dental, functional and mild bony ones will use a six-month fixation device together with skin traction to solve the anastomosis. In case of maxillary hypoplasia, rapid maxillary expansion + anterior traction will be performed. In the case of maxillary hypoplasia in the early permanent dentition, one year of maxillary rapid expansion + anterior traction will be performed before fixed orthodontic treatment. In the case of mandibular protrusion, it can be corrected by removing the mandibular wisdom teeth and then applying implant nails. Even if some bony Class III malocclusion is not serious at a young age (10-12 years old), and two years of orthodontic treatment has been completed, and the occlusion of the front teeth reaches normal, with the onset of growth spurts, especially in boys at the age of 14 years old (who may grow more than 10cm in 1 year), the lower jaw may overgrow in one year (which may be an additional 3-4mm in 1 year), leading to recurrence of an anterior synechiae. If this situation is encountered, the less serious ones need to be re-corrected, and the serious ones can only continue to be observed until, after the age of 18, orthognathic surgery. And surgical patients usually have 1 year of preoperative orthodontics and 6 months of postoperative orthodontics before surgery. In severe non-surgical patients, if there is maxillary hypoplasia, we may also provide orthodontic treatment by expanding the arch before traction before the onset of puberty, in order to reduce the complexity and trauma of the surgery.