Early orthodontic correction is beneficial for the correction of osseous retrognathism. Therefore, doctors will tell patients, including the parents of patients suffering from jaw rejection, that early correction of bony jaw rejection will be more effective. The specific time needs to be treated according to the following circumstances: 1, early milk jaw period: the earliest can be corrected at the age of about three years old, individual patients such as boys and girls have differences, boys can be appropriate later, girls as early as possible, the earliest time for correction is two and a half years old can do correction; 2, the replacement jaw period: in the early replacement jaw to solve the bony problem, the advantages of the patient’s bones may be easy to change The disadvantage of orthodontic bone jaw correction is that the teeth are in the process of replacement, correction of patients with skeletal problems can lead to premature loss of milk teeth; 3, permanent period: in the permanent period, mild and moderate bone jaw, generally 11-12 years old patients are recommended for correction in the early permanent teeth. For individual adult patients with very strong bony retrusion, it is recommended that the skeletal problems be solved after the age of 18, together with orthodontics, so as to solve the skeletal problems of teeth.