1. Department of Oral Medicine and Diagnosis, Research Institute of Oral Science, College of Dentistry, Gangneung-Wonju National University, Gangneung, Korea.
2. Department of Oral and Maxillofacial Radiology, Research Institute of Oral Science, College of Dentistry, Gangneung-Wonju National University, Gangneung, Korea.
3. Department of Dental Hygiene, Research Institute of Oral Science, College of Dentistry, Gangneung-Wonju National University, Gangneung, Korea.