Ye-Ping Li1, Ren-Kai Liu1, Bing Shi2, Cheng-Hao Li2. 1. State Key Laboratory of Oral Disease, West China College of Stomatology. 2. State Key Laboratory of Oral Disease, West China College of Stomatology, and Department of Cleft Lip and Palate Surgery, West China Stomatological Hospital, Sichuan University, Chengdu, People's Republic of China.