1. Department of Biomedical Health Science, Graduate School, Dong-Eui University, Changwon, Korea
2. Oral Hygiene Science Research Institute, Dong-Eui University, Changwon, Korea
3. Department of Dental Hygiene, Dong-Eui University, Busan, Korea
4. Department of Dental Hygiene, Masan University, Changwon, Korea