1. College of Stomatology, Hospital of Stomatology, Guangxi Medical University, No. 10 Shuangyong Road, Nanning, Guangxi, 530021, PR China
2. Department of Anesthesiology, Central Hospital of Shaoyang, Shaoyang, Hunan, 422000, China
3. Department of Implantology, Anyang Sixth People's Hospital, Anyang, Henan, 455000, China
4. Guangxi Medical University, Nanning, Guangxi, 530021, China