1. Department of Orthodontics, School of Stomatology, Peking University, No. 22 Zhongguancun South Road, Haidian District, Beijing 100081, China
2. Central Laboratory, School of Stomatology, Peking University, Beijing 100081, China
3. Beijing Bioyong Technologies Inc., Beijing 100085, China
4. Clinical Laboratory, Beijing Haidian Maternal & Child Health Hospital, Beijing 100080, China