1. State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, People's Republic of China.
2. National Engineering Laboratory for Oral Regenerative Medicine, West China Hospital of Stomatology, Sichuan University, Chengdu, People's Republic of China.
3. Department of Oral and Maxillofacial Surgery, West China School of Stomatology, Sichuan University, Chengdu, People's Republic of China.
4. Department of Periodontics, West China School of Stomatology, Sichuan University, Chengdu, People's Republic of China.
5. Department of Pedodontics, West China School of Stomatology, Sichuan University, Chengdu, People's Republic of China.