1. Department of Implantology, Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou, P. R. China;
2. Department of Oral Medicine, Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou, P. R. China
3. Department of Oral and Maxillofacial Surgery, Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou, P. R. China;