1. Department of Medical Ultrasound, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, China
2. College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu, 610065, China
3. West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China