1. Department of Dental science, Graduate School, Chonnam National University, Gwangju 61186, Republic of Korea
2. Department of Oral and Maxillofacial Radiology, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea
3. Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju 61186, Republic of Korea