1. Department of Dental Hygiene, Chodang University, Muan‑ro, Muan‑eup, Muan 534‑701, Republic of Korea
2. Department of Oral Biochemistry, College of Dentistry, Chosun University, Dong‑gu, Gwangju 501‑759, Republic of Korea
3. CStech Research Institute, Gwangju 61007, Republic of Korea