1. Department of Conservative Dentistry, Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Korea.
2. Division of Restorative Dentistry, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Canada.
3. Department of Conservative Dentistry, School of Dentistry, Kyung Hee University, Seoul, Korea.
4. Department of Oral Microbiology and Immunology, Dental Research Institute and BK21 Plus Program, School of Dentistry, Seoul National University, Seoul, Korea.