1. Institute of Biomedical Engineering, Center of West China of Medical Sciences, West China College of Basic Medicine and Forensic Medicine, Sichuan University, Chengdu, The People's Republic of China.
2. Department of Oral and Maxillofacial Surgery, West China College of Stomatology, Sichuan University, Chengdu, The People's Republic of China.
3. Department of Orthodontics, West China College of Stomatology, Sichuan University, The People's Republic of China.