Article History
Received: 22 February 2017
Accepted: 31 October 2018
First Online: 20 November 2018
Authors’ information
: The lists and informations of all authors is provided on the title page.
: This study was approved by the Institutional Review Board of the School of Medicine, Ewha Womans University (Approval no. 15–11-01). The written form of consent and the questionnaire in Korean and English used in this study are attached on the additional files section.
: All participants, in consent to participate, allowed the identification of their personal information, including teeth images.
: The authors declare that they have no competing interests.
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