Dentition, dental health habits, and dementia: the Leisure World Cohort Study.

OBJECTIVES: To explore the association between dentition and dental health behaviors and incident dementia. DESIGN: Longitudinal cohort. SETTING: Leisure World, Laguna Hills, CA; a retirement community. PARTICIPANTS: Five thousand four hundred sixty-eight older (median age 81) adults followed from 1992 to 2010. MEASUREMENTS: Questions regarding dental health focused on number of natural teeth, dentures worn, number of visits to a dentist, and oral health habits. Dementia status was determined from in-person evaluations, follow-up questionnaires, hospital data, and death certificates. Estimates of dementia risk were calculated using Cox regression analysis in men and women separately. RESULTS: Men with inadequate natural masticatory function who did not wear dentures had a 91% greater risk of dementia than those with adequate natural masticatory function (≥ 10 upper teeth and ≥ 6 lower teeth). This risk was also greater in women but not significantly so. Dentate individuals who reported not brushing their teeth daily had a 22% to 65% greater risk of dementia than those who brushed three times daily. CONCLUSION: In addition to helping maintain natural, healthy, functional teeth, oral health behaviors are associated with lower risk of dementia in older adults.