1. Department of Orthodontics,
Peking University School and Hospital of Stomatology, National Engineering
Laboratory for Digital and Material Technology of Stomatology, and
Beijing Key Laboratory of Digital Stomatology, Peking University, 22
Zhongguancun South Avenue, Haidian District,
Beijing 100081, P. R. China
2. State Key Laboratory of Applied Organic Chemistry, Key Laboratory
of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province
and Department of Chemistry, Lanzhou University, Lanzhou 730000, P. R. China
3. CAS Key Laboratory of Bio-inspired Materials and Interfacial Science,
CAS Center for Excellence in Nanoscience, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China