[1] Univ Geneva, Univ Clin Dent Med, Div Gerodontol & Removable Prosthodont, 1 Rue Michel Servet, CH-1211 Geneva 4, Switzerland
[2] Univ Bern, Sch Dent Med, Div Gerodontol, Bern, Switzerland
[3] Queens Univ Belfast, Ctr Publ Hlth, Belfast, Antrim, North Ireland
[4] Univ Hosp Geneva, Dept Internal Med Rehabil & Geriatr, Serv Geriatr, Thonex, Switzerland