1. State Key Laboratory of Oral Diseases National Center for Stomatology National Clinical Research Center for Oral Diseases Department of Dental Technology West China Hospital of Stomatology Sichuan University Chengdu PR China
2. Department of Biologic and Materials Sciences & Prosthodontics University of Michigan School of Dentistry Ann Arbor Michigan USA
3. Department of Dental Implantology Guiyang Hospital of Stomatology Guiyang Guizhou China
4. Department of Prosthodontics University of Ferrara Ferrara Italy