1. Department of Periodontology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China
2. Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
3. Department of Periodontology, Guangdong Provincial Hospital of Stomatology, Stomatological Hospital of Southern Medical University, Guangzhou, China