1Department of Implantology, Graduate School of Clinical Dentistry, Ewha Womans University, Korea.
2Department of Periodontology, Graduate School of Clinical Dentistry, Ewha Womans University, Korea.
3Department of Periodontology, School of Medicine, Ewha Womans University, Korea.
Corresponding author: Seoung-Ho Lee, Department of Periodontology, School of Medicine / Graduate School of Clinical Dentistry, Ewha Womans University, 911-1 Mok-6-dong, Yangcheon-gu, Seoul, Korea. Tel: +82-2-2650-5680, Fax: +82-2-2650-5764, perio772@ewha.ac.kr