1. State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China
2. Department of Prosthodontics, West China School of Stomatology, Sichuan University, No. 14, Section 3, Renmin Nanlu, Chengdu 610041, China