Funding for this research was provided by:
National Natural Science Foundation of China (81500841)
Scientific Research in the Public Interest (201502002)
Text and Data Mining valid from 2018-05-21
Received: 12 September 2017
Accepted: 7 May 2018
First Online: 21 May 2018
Ethics approval and consent to participate
: This survey was approved by the Stomatological Ethics Committee of the Chinese Stomatological Association (Approval No. 2014–003) and the Ethics Committee of the West China Hospital of Stomatology at Sichuan University.
: The authors declare that they have no competing interests.
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