1. Department of International and Community Oral Health Tohoku University Graduate School of Dentistry Sendai Japan
2. Department of Social Preventive Medical Sciences, Center for Preventive Medical Sciences Chiba University Chiba Japan
3. Department of Gerontological Evaluation, Center for Gerontology and Social Science National Center for Geriatrics and Gerontology Obu Japan
4. Department of Oral Health Promotion Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University Tokyo Japan
5. Division for Regional Community Development Tohoku University Graduate School of Dentistry Sendai Japan