1. Center of Digital Dentistry, Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Center of Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, NHC Research Center of Engineering and Technology for Computerized Dentistry, Beijing, P.R. China.
2. Shanxi Province Key Laboratory of Oral Diseases Prevention and New Materials, Taiyuan, P.R. China.