1. First Clinical Division, Peking University School and Hospital of Stomatology, Beijing, China
2. Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing, China
3. Second Clinical Division, Peking University School and Hospital of Stomatology, Beijing, China
4. National Center of Stomatology; National Clinical Research Center for Oral Diseases, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China