Funding for this research was provided by:
National Research Foundation of Korea (2017R1D1A1B03032132, 2014R1A1A1003559)
Text and Data Mining valid from 2018-02-12
Received: 21 November 2017
Accepted: 23 January 2018
First Online: 12 February 2018
Ethics approval and consent to participate
: All participants provided informed consents. The present study was approved by the Chonnam National University Dental Hospital Institutional Review Board (CNUDH-2015-003).
: Not applicable.
: The author declares that there are no competing interests.
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