[1] Tokyo Metropolitan Inst Geriatr & Gerontol, Tokyo, Japan
[2] Hokkaido Univ, Fac Dent Med, Dept Prevent Dent, Kita 13,Nishi 7,Kita Ku, Sapporo, Hokkaido 0608586, Japan
[3] Hokkaido Univ, Grad Sch Dent Med, Kita 13,Nishi 7,Kita Ku, Sapporo, Hokkaido 0608586, Japan
[4] Univ Tokyo, Inst Gerontol, Tokyo, Japan
[5] Osaka Univ, Grad Sch Dent, Dept Removable Prosthodont & Gerodontol, Osaka, Japan
[6] Tokyo Dent Coll, Dept Removable Prosthodont & Gerodontol, Tokyo, Japan
[7] Tokyo Med & Dent Univ, Grad Sch Med & Dent Sci, Dept Gerodontol & Oral Rehabil, Tokyo, Japan
[8] Univ Tokyo, Grad Sch Med, Dept Geriatr Med, Tokyo, Japan
[9] Natl Ctr Geriatr & Gerontol, Aichi, Japan
[10] Univ Tokyo, Inst Future Initiat, Tokyo, Japan