Non-surgical orthodontics, also known as orthodontics, generally refers to traditional braces. Of course, lingual appliances are also developing now, but the principle is the same. They all rearrange their teeth with the help of external forces. It takes a long time to correct braces, generally about 2 years, and the best operation time is 12- 18 years old, which has a good effect on odontogenic buck teeth and ground cover, but the alveolar buck teeth and ground cover can not achieve the expected effect and must be corrected by surgery.