1 Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi Zhuang Autonomous Region, People's Republic of China.
2 Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi Zhuang Autonomous Region, People's Republic of China. chm8284@163.com.