1, for most malocclusion can be orthodontic treatment in the early permanent teeth, girls generally in 11 to 13 years old, boys generally in 12 to 15 years old. At this time, the end of tooth replacement, the permanent tooth row is basically established, the craniofacial soft and hard tissue development still has some potential, good tissue metabolic function, the most significant effect of tooth movement, so this period is the “golden period” of orthodontic treatment. 2, for the anticlinal (commonly known as “envelope”, “pocket teeth”) this malocclusion affecting the development of the jaw bone to be treated early. The best orthodontic treatment time for the period of the baby teeth is about 4 years old, when the roots of the baby teeth have been fully developed and have not begun to resorb, the correction effect is better, but there are some patients in the period of the permanent teeth or early relapse, need to be closely observed. The best orthodontic treatment time should be carried out after the basic development of permanent incisor roots is completed, about 8 to 9 years old. Maxillary plane fit cushion 3, children’s oral condition needs parents’ attention from time to time, if children appear caries, or early loss of milk teeth, finger sucking, tongue spitting, biting the lower lip, mouth breathing and other bad oral habits, regardless of age, once found, parents need to take their children to the hospital for examination as soon as possible, early intervention, certain blocking orthodontic treatment, so as not to cause or aggravate malocclusion. 4, for early bony malocclusion, such as underdevelopment of the upper jaw (“ground envelope”), overdevelopment of the upper jaw, underdevelopment of the lower jaw (“small chin”), narrowing of the upper dental arch, deviation (crooked chin), etc. can be before and during the growth spurt Wearing functional orthodontic appliances can promote or inhibit the growth of the corresponding jaws, so that the upper and lower jaws can develop in close coordination. Generally, orthodontic treatment is performed 1-3 years before the peak of youthful growth, about 10-12 years old (the peak for males is about 2 years later than for females). Later conventional orthodontic treatment is often required after wearing functional orthodontic appliances. 5, for patients with severe bony malocclusion with obvious genetic tendency, it is necessary to wait until the jaws are fully developed (after about 18-20 years old) for combined orthodontic and orthognathic surgery in order to achieve satisfactory results.