1Department of Periodontology, College of Dentistry, Chosun University, Korea.
2Oral Biology Research Institute, College of Dentistry, Chosun University, Korea.
Corresponding author: Hyun-Seon Jang, Department of Periodontology, College of Dentistry, Chosun University, 421 Seosuk-dong, Dong-ku, Gwang-ju, 501-825, South Korea. periojang@chosun.ac.kr