1. Graduate Prosthodontics, State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China Hospital
2. Department of Stomatology, the Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan, China
3. State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Chengdu, China and Department of Oral Prosthodontics