Funding for this research was provided by:
National Research Foundation of Korea (NRF-2018R1A5A2023879, NRF-2017R1A2B4005588)
Text and Data Mining valid from 2019-08-12
Received: 11 June 2019
Accepted: 22 July 2019
First Online: 12 August 2019
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of Pusan National University Dental Hospital (IRB No. PNUDH-2019-006), and written, informed consent was obtained for all study participants prior to data collection.
: Not applicable.
: The authors declare that they have no competing interests.