1 Division of Oral Health Policy, Bureau of Health Policy, Ministry of Health and Welfare, Sejong, Korea.
2 Dental Policy/Professional Affairs, Korean Dental Association, Seoul, Korea.
3 Korean Academy of Periodontology, Seoul, Korea.
4 Department of Periodontology, The Institute of Oral Health Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. pkoyang@skku.edu.