Funding for this research was provided by:
National Natural Science Foundation of China (81670948)
China Rehabilitation Research Center (2017ZX-03)
Received: 30 December 2017
Accepted: 19 December 2018
First Online: 28 January 2019
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of the Beijing Stomatological Hospital at the Capital Medical University (Ethics Review No. 2011–02); all patients provided written informed consent.
: Not applicable.
: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this paper. All authors read and approved the final manuscript prior to publication.
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