1. Department
of Cariology and Endodontology, National Engineering Laboratory for
Digital and Material Technology of Stomatology, Beijing Key Laboratory
of Digital Stomatology, Peking University School and Hospital of Stomatology, Beijing 100081, P. R. China
2. Department of Orthodontics,
National Engineering Laboratory for Digital and Material Technology
of Stomatology, Beijing Key Laboratory of Digital Stomatology, Peking University School and Hospital of Stomatology, Beijing 100081, P. R. China
3. State Key Laboratory of Polymer Physics
and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China