Article History
Received: 23 November 2018
Accepted: 4 February 2019
First Online: 1 March 2019
Ethics approval and consent to participate
: This study was approved by the institutional review board of Gangneung-Wonju National University Dental Hospital (IRB No. 2017-003).
: Written informed consent was obtained from the patients or patient’s guardian for including the data of radiographic images in this study.
: The authors declare that they have no competing interests.
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