1. Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University Engineering Research Center of Oral Biomaterials and Devices of Zhejiang Province Hangzhou 310000 China
2. Faculty of Dentistry The University of Hong Kong Hong Kong, SAR 999077 China
3. Clinic of Operative Dentistry, Periodontology and Preventive Dentistry Saarland University 66424 Homburg Saarland Germany