1. Department of Oral Health, Graduate School of Health and Welfare, Dankook University, Cheonan, Korea
2. Department of Dental Hygiene, Andong Science College, Andong, Korea
3. HBD Division, Amorepacific R&D Center, Yongin, Korea
4. Department of Preventive Dentistry, College of Dentistry, Dankook University, Cheonan, Korea