1. Department of Oral and Maxillofacial Radiology, Chosun University, Gwangju 61452, Korea
2. Institute of Dental Science, Chosun University, Gwangju 61452, Korea
3. Departments of Oral and Maxillofacial Surgery, School of Dentistry, Chosun University, Gwangju 61452, Korea
4. Departments of Prosthodontics, School of Dentistry, Chosun University, Gwangju 61452, Korea