The best time for children’s orthodontic treatment depends on the type of deformity, the details are as follows: 1, 3-5 years old: anterior teeth, commonly referred to as “enameled”, should be orthodontic at the age of 3-5 years old; 2, 6-12 years old: serious facial deformities, such as bony deformities, children with tongue extension, tongue biting, biting the lower lip habits, should be orthodontic at the age of 6-12 years old; 3, 12-13 years old: permanent teeth have all erupted, the growth state is more vigorous, most dental deformities can be orthodontic in this period; 4, after 18 years old: serious malocclusion due to genetic disease should be orthognathic and orthopedic treatment after the age of 18 years old.