1. Department of Pediatric Dentistry, Kyushu University Faculty of Dental Science, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan;
2. Section of Pediatric Dentistry, Division of Oral Health, Growth & Development, Faculty of Dental Science, Kyushu University;
3. Department of Internal Medicine I, School of Medicine, Oita Medical University, Japan; and
4. Department of Nutrition Sciences, Graduate School of Health and Nutrition Science, Nakamura Gakuen University, Japan;