Liu, Min
Yun, Qingping
Zhao, Mei
Chen, Wei
Zhang, Hui
Hou, Wei
Chang, Chun
Article History
Received: 21 December 2020
Accepted: 17 March 2021
First Online: 24 March 2021
Declarations
:
: This study protocol was approved by the Ethics Committee of the Chinese Stomatological Association (Approval no.2014–003) and was performed in accordance with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. Informed consent was obtained from each child’s parent and/or legal guardian.
: Not applicable.
: The authors declare that they have no competing interests.