Studies show that 80% or more of the population expresses dissatisfaction with the current state of their teeth, and many people cannot accept the symptoms of their malocclusion, misalignment of teeth, diastema (anticuspension), and other dental irregularities. Teeth are not only a person’s best face, its mutilations and irregularities will also affect the normal chewing and speaking functions, so for the teeth correction is not to be ignored. However, many people are concerned about whether they have passed the best time for orthodontic treatment. What is the best age for orthodontic treatment? And will orthodontic treatment for adults affect the efficacy of teeth? Generally speaking, adolescence, i.e. 12-14 years old, is the best age for orthodontic treatment. after 18 years old, due to the basic completion of growth and development, the effect of orthodontic treatment is not as good as that of childhood and adolescence. Children’s age for orthodontic treatment of malocclusion: 12-14 years old for boys and 11-13 years old for girls, but each child’s growth and development has individual differences and cannot be generalized. Correction during the growth spurt is the shortest course of treatment and has the best effect. If there is a mild dental irregularity during the period of tooth replacement (7-12 years old), experts suggest that there is no need to rush to orthodontic treatment. Because of this period of rapid bone development, changes, general malocclusion, malocclusion may be improved, but may also be aggravated. However, there are the following cases that should be corrected: antimandibular anterior teeth, malocclusion caused by multiple teeth, severe misalignment of individual teeth, and abnormal relationship between upper and lower arches. In children, the following dental diseases need to be corrected immediately during the period of milk teeth (3-7 years old): anterior antomandibularity, mandibular protrusion, posterior antomandibularity, and all bad oral habits that interfere with the normal development and function of the jaws and face. Even adults can still straighten their teeth without worrying that straightening their teeth in adulthood will cause harm to their teeth. In fact, as long as the teeth appear to be irregular will produce different degrees of damage to the teeth in the schedule life, over time, before irreversible damage to the teeth.