1. Former resident, Division of Orthodontics, Department of Dentistry, College of Medicine, Ewha Womans University, Seoul, Korea.
2. Professor, Division of Orthodontics, Department of Dentistry, College of Medicine, Ewha Womans University, Seoul, Korea.
3. Associate professor, Department of Preventive Medicine, College of Medicine, Ewha Womans University, Seoul, Korea.
4. Assistant professor, Division of Orthodontics, Department of Dentistry, College of Medicine, Ewha Womans University, Seoul, Korea.