1 Department of Orthodontics, Seoul St. Mary's Hospital, Seoul, Korea. kook2002@catholic.ac.kr.
2 Department of Orthodontics, Seoul St. Mary's Hospital, Seoul, Korea.
3 Postgraduate Orthodontic Program, Arizona School of Dentistry & Oral Health, A.T. Still University, Mesa, AZ; Graduate School of Dentistry, Kyung Hee University, Seoul, Korea.
4 Private Practice of Orthodontics in Seoul, Korea.