1. Medical Professor, Department of Dentistry, College of Medicine, Inha University, Korea.
2. Graduate Student, Department of Orthodontics, College of Dentisrty, Yonsei University, Korea.
3. Professor, Department of Orthodontics, College of Dentisrty, Yonsei University, Korea.
4. Associate Professor, Department of Orthodontics, College of Dentisrty, Yonsei University, Korea.