The teeth are misshapen, with the lower teeth elongated and covering the front upper teeth, the upper teeth are obviously crowded and uneven, the right upper cusp is not erupted, and the individual baby teeth are not lost. This is a common type of malocclusion. The medical principle for the correction of retrusion is to eliminate the cause as early as possible, early orthodontic treatment can receive good orthodontic effect, and can prevent the development of malformation to serious. The early milk teeth (milk teeth) “enameled” or individual permanent front teeth “enameled” children are mostly dental reasons, but if not treated early, jaw growth due to long-term obstruction may lead to restricted development of the upper jaw, further aggravating “The facial deformity of “concave face” and “curved moon face” will become more and more serious and difficult to treat. Therefore, children with “encephalitis” should be treated as early as possible to prevent the development of the deformity before it is too late. If the baby teeth are mildly retruded, it can be temporarily uncorrected, and when the baby teeth are lost and replaced by permanent teeth, some of the retruded jaw deformity can be corrected by itself. In the case of severe, significant jaws, it is better to treat them at the age of 4 years. The replacement period and early permanent teeth, jaw and facial growth and development, anti-jaw deformity, such as timely correction, can receive twice the result with half the effort, and can timely interrupt the abnormal growth and development of the jaws, is the key period of correction of anti-jaw. Otherwise, we can only achieve good results by pulling fewer teeth or orthognathic surgical treatment.