1. Professor and Chair, Postgraduate Orthodontic Program, Arizona School of Dentistry & Oral Health, A.T. Still University, Mesa, Arizona, USA.
2. International Scholar, Graduate School of Dentistry, Kyung Hee University, Seoul, Korea.
3. Former Resident, Department of Orthodontics, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Korea.
4. Resident, Department of Orthodontics, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Korea.
5. Research Assistant Professor, College of Medicine, The Catholic University of Korea, Seoul, Korea.
6. Visiting Professor, Department of Postgraduate Studies, Universidad Autonóma del Paraguay, Asunción, Paraguay.
7. Professor, Department of Orthodontics, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Korea.
8. Assistant Professor, Department of Orthodontics, School of Dentistry, Kyungpook National University, Daegu, Korea.
9. Associate Professor, Department of Orthodontics, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Korea.