1. Graduate School, The Catholic University of Korea, Seoul, Korea.
2. Department of Orthodontics, College of Medicine, The Catholic University of Korea, Seoul, Korea.
3. Department of Postgraduate Studies, the Universidad Autonóma del Paraguay, Asunción, Paraguay.
4. Postgraduate Orthodontic Program, Arizona School of Dentistry & Oral Health, A.T. Still University, Mesa, AZ, USA.
5. Graduate School of Dentistry, Kyung Hee University, Seoul, Korea.
6. Department of Orthodontics, Oral Biology Research Institute, Kyung Hee University School of Dentistry, Seoul, Korea.
7. Formal Adjunct Professor at UCLA and Clinical Professor at USC Orthodontics Currently Private Practice in Los Angeles, CA, USA.
8. Department of Orthodontics, Seoul St. Mary's Hospital, The Catholic University of Korea, Seoul, Korea.