Oral health and risk of cognitive disorders in older adults: A biannual longitudinal follow‐up cohort

Abstract Background Oral health may be associated with cognitive disorders such as mild cognitive impairment or dementia. Objective This study elucidates the effects of oral health conditions on the progression of cognitive disorders. Methods Data were collected from 153 participants of the Korean Longitudinal Study on Cognitive Aging and Dementia cohort who completed the longitudinal dental examinations and cognitive function assessments using the three‐wave biannual survey. We analysed the relationship between dental factors and the conversion of cognitive function. Results The ratio of maxillary removable partial denture use ( p = .03) was high in the converter and mild cognitive impairment/dementia groups. The low‐grade ratio of posterior masticatory performance increased in the converter and mild cognitive impairment/dementia groups (modified Eichner index 2, p = .04). The mild cognitive impairment/dementia group had a higher rate of complete mandibular denture use ( p < .001). The converter and mild cognitive impairment/dementia groups had fewer remaining teeth ( p < .05) or removable prostheses ( p < .01) than the normal group. Conclusions Masticatory performance is associated with the conversion of cognitive disorders. Our findings suggest that oral health management can help delay the progression of cognitive disorders.