1. State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, National Clinical Research Center for Oral Diseases, Shaanxi Clinical Research Center for Oral Diseases, Department of Orthodontics, School of Stomatology, The Fourth Military Medical University , Xi’an, Shaanxi , China
2. Department of Health Services School of Preventive Medicine, Fourth Military Medical University , Xi’an, Shaanxi , China
3. Department of Stomatology, Xi’an First Hospital , Xi’an, Shaanxi , China
4. School and Hospital of Stomatology, Shanxi Medical University , Taiyuan, Shanxi , China