It is often believed that the best age for orthodontic treatment is 12-15 years old, which is incomplete and has even caused miscommunication for some patients. Because different malocclusion at different ages or in different periods of dental growth and development have an optimal time for correction. For example: First, the correction of milk teeth period 1, milk teeth period of anti-collision: its characteristic is that the lower jaw will grow with the growth and development of the larger and larger. 2.Mastodontic protrusion of the upper jaw: characterized by the growth and development of the lower jaw is impeded, more and more backward recession, more and more small 3.Mastodontic deep overjet and front teeth bite too deep: even the upper and lower bite can not see the lower front teeth and so on. Where the growth and development of the maxillofacial growth and development of all kinds of cases of correction of the best time is 3-5 years old, usually in 3 to 6 months or so can be corrected, of course, can not be a long time to correct. If after this age, the correction time is long and the effect may not achieve the desired results. Second, the orthodontic period 1, mild dental crowding and crowding degree in 3-5mm, if timely orthodontic intervention to take full advantage of the gap between the replacement of milk teeth – permanent teeth, you can avoid the removal of permanent teeth after the replacement of teeth. 2, severe dental crowding can be based on genetic factors, the size of the teeth of the prediction and crowding degree of about 10mm, can also be early intervention. By sequential extraction and pre-extraction of individual baby teeth and permanent teeth, a perfect alignment can be established even without orthodontic treatment. Third, the best time for orthodontic treatment at 12-15 years old Most children and teenagers enter the permanent teeth stage at this age, and this stage is the peak of children’s growth and development, girls a little earlier, boys a little later, due to a variety of reasons for the appearance of malocclusion, it should be routine orthodontic treatment; however, for the part of the jawbone deformity that misses the optimal time for orthodontic treatment, we can only wait until 18 years old to carry out the orthodontic orthoprosthetic diagnosis and treatment. Treatment. Adult orthodontic treatment With the improvement of people’s material and cultural level, more and more adults have increasing demand for orthodontic treatment, and now the level of orthodontic technology has been able to fully meet their requirements, therefore, the optimal age cannot be generalized, but should be analyzed and given the optimal time and age for orthodontic treatment by the professional doctors after detailed examination, which is reasonable and scientific.