Orthodontists at home and abroad generally agree that early detection and early treatment of malocclusion should be the principle, and the best time for orthodontic treatment is determined according to the specific situation of each patient’s malocclusion and the state of growth and development. Most patients often have to go through a “two-phase” treatment, that is, early (before 12 years old, before tooth replacement) orthodontic treatment and the second phase (after 12 years old, when the milk teeth are replaced by permanent teeth) of comprehensive orthodontic treatment, early treatment can receive twice the effect with half the effort. In particular, some diseases, such as “encephaloplasty” (retrusion), “small chin” (receding jaw), deviated jaw (facial development asymmetry) and other deformities, if not treated early, will leave traces of the original deformity, and the later the treatment, the heavier the traces left. Therefore, we often see children who have “encephalocele”, although the teeth are receding, the facial shape still looks like “encephalocele”. In the past, people thought that around 12 years old is the best time to correct teeth, this view has left a deep impression in the minds of many people, including oral surgeons, in fact, the view now seems to be not completely correct, and in a sense is harmful, many patients therefore delayed treatment, and in serious cases, only with the help of surgery. If the orthodontic specialist diagnoses that the malformation of teeth and bones caused by bad oral habits, abnormal tooth replacement, heredity and other factors, such as “ground bag sky”, “small chin”, deviated jaws, open jaw, tooth interruption, early loss of milk teeth, late eruption of permanent teeth, serious tooth position If the malocclusion is only simple, it should be treated early, and the earlier the better. If the malocclusion is only a simple dental problem, the best time to correct it is from 9 to 14 years old for females and 12 to 18 years old for males. If the malformation is an abnormal function of teeth or facial muscles, asymmetry of facial bone development, underdevelopment, overdevelopment, or “envelope”, “small chin”, etc., it is better for females before 8~9 years old and for males before 10~11 years old. If the skeletal deformity is not seen until the growth has basically stopped (i.e. after the age of 15), then simple orthodontic methods cannot solve the problem and must be combined with surgical procedures to achieve the desired effect. If the malocclusion is only a dental problem, such as “tiger teeth”, misalignment of teeth, misalignment of teeth, gaps, etc., then even if the best treatment time is missed, adult orthodontics can be carried out, and the same satisfactory results can be achieved. Finally, parents are reminded to take their children to the orthodontic specialist once every six months so that problems can be detected and treated in time.