1. Department of Prosthodontics Peking University School and Hospital of Stomatology Beijing China
2. 4th Division Peking University Hospital of Stomatology Beijing China
3. National Engineering Lab for Digital and Material Technology of Stomatology Peking University School and Hospital of Stomatology Beijing China
4. National Clinical Research Center for Oral Diseases Beijing China
5. Central Laboratory Peking University School and Hospital of Stomatology Beijing China