Su, Hongru
Yang, Renren http://orcid.org/0000-0003-0859-3448
Deng, Qinglong
Qian, Wenhao
Yu, Jinming
Article History
Received: 9 March 2017
Accepted: 28 May 2018
First Online: 19 June 2018
Ethics approval and consent to participate
: The study protocol was approved by the Ethics Committee of Xuhui District Dental Centre. Written informed consent was obtained from children’s guardians before the study.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.