1. Department of Preventive Dentistry, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan
2. Department of Oral Frontier Biology, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan
3. Department of Dentistry and Oral Surgery, Sakai, Osaka, Japan
4. Department of Internal Medicine, Center for Diabetes Mellitus, Osaka Rosai Hospital, Sakai, Osaka, Japan