Gu, Yechen
Sun, Chao
Wu, Daming http://orcid.org/0000-0002-2326-9630
Zhu, Qingping
Leng, Diya
Zhou, Yang
Funding for this research was provided by:
a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD2014-37)
the Natural Science Foundation of Jiangsu Province (BK20151560)
the Cadre health care research of Jiangsu Province (BJ15031)
the Scientific Research of Jiangsu Provincial Commission of Health and Family Planning (H2017050)
Article History
Received: 21 July 2018
Accepted: 20 September 2018
First Online: 3 October 2018
Ethics approval and consent to participate
: This study was approved by the Ethical Committee Department, the Affiliated Stomatological Hospital of Nanjing Medical University (PJ2015–047-0011). Informed consent was obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.
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