1. Department of Special Needs Dentistry Division of Hygiene and Oral Health Showa University School of Dentistry Tokyo Japan
2. Department of Critical Care Medicine and Dentistry Division of Medically Compromised Geriatric Dentistry Graduate School of Dentistry Kanagawa Dental University Yokosuka Japan
3. Tokyo Metropolitan Institute of Gerontology Tokyo Japan
4. National Center for Geriatrics and Gerontology Aichi Japan
5. Department of Oral Health Care Education Graduate School of Medical and Dental Science Tokyo Medical and Dental University Tokyo Japan
6. Department of Oral and Maxillofacial Surgery Tokyo Metropolitan Institute of Gerontology Tokyo Japan