1. The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine, Ministry of Education, School and Hospital of Stoma-tology; Wuhan University; 237 Luoyu Road Wuhan 430079 PR China
2. Department of Oral and Maxillofacial Trauma and Plastic Surgery; School and Hospital of Stomatology; Wuhan University; 237 Luoyu Road Wuhan 430079 PR China
3. Key Laboratory of Oral Medicine; Guangzhou Institute of Oral Disease; Stomatological Hospital of Guangzhou Medical University; Guangzhou 510140 PR China