* Corresponding authors

^a 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, P. R. China
E-mail: luoqiaojie@zju.edu.cn
Fax: +8657187217433
Tel: +8657188208151

^b Guangxi Key Laboratory of Oral and Maxillofacial Rehabilitation and Reconstruction, College of Stomatology, Guangxi Medical University, Nanning 530021, P. R. China