Article History
Received: 14 November 2017
Accepted: 17 April 2018
First Online: 24 April 2018
Ethics approval and consent to participate
: The research team sent the consent forms for oral examinations and surveys to students’ parents/guardians with a brief introduction. Only students who returned completed consent forms from their parents/guardians were included in the study.The Institutional Review Board in Gangneung-Wonju National University Dental Hospital reviewed and approved this study (GWNUDH IRB-2011-1-3).
: The authors declare that they have no competing interests.
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