1. Hunan Key Laboratory of Oral Health Research & Human 3D Printing Engineering Research Central of Oral Care & Hunan Clinical Research Center Of Oral Major Diseases and Oral Health & Xiangya Stomatological Hospital & Xiangya School of Stomatology, Central South University, Changsha, 410008 Hunan, China
2. The Republican General Teaching Hospital, Taiz Health & Population Office, Yemen