1. State Key Laboratory of Oral Diseases; West China Hospital of Stomatology, Sichuan University; Chengdu China
2. Department of Stomatology; Nan Chong Central Hospital, Second Clinical Medical College of Chuan Bei Medical College; Nanchong China
3. Department of Prosthodontics & Implantology, Guizhou Medical University School of Stomatology; Guizhou Medical University; Guizhou China
4. State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Head and Neck Oncology; West China Hospital of Stomatology, Sichuan University; Chengdu China
5. Dept of Growth, Development and Structure; Southern Illinois University, School of Dental Medicine; Alton Illinois USA