Zhao, Xu
Gao, Wei
Liu, Feng
Article History
Received: 21 March 2018
Accepted: 25 August 2018
First Online: 14 September 2018
Ethics approval and consent to participate
: The study plan and consent to participate were reviewed and approved by the ethics committee of Peking University, School and Hospital of Stomatology (PKUSSIRB-201733019). The study complies with the relevant Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) Checklist (Additional fileInternalRef removed).
: Not applicable.
: The authors declare that they have no competing interests.
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