1. Department of Oral Histology and Developmental Biology, College of Dentistry, Chosun University, Gwangju 61452, Korea
2. Department of Dental Hygiene and Institute of Basic Science for Well-Aging, College of Health Science, Youngsan University, Yangsan 50510, Korea
3. Department of Dental Hygiene, Yeungnam College, Daegu 42415, Korea
4. Department of Dental Hygiene, College of Health Science, Eulji University, Seongnam 13135, Korea