Association between dental implantation and dementia: a nationwide population-based study

Abstract

Background: Dementia is a growing global health concern with an increasing focus on identifying modifiable risk factors. Emerging evidence suggests a potential link between oral health and cognitive function in older adults. This study aimed to investigate the association between dental implants and the risk of dementia in patients with mild cognitive impairment (MCI) using nationwide data from the Korean National Health Insurance Service. Methods: We conducted a large-scale population-based cohort study using data from 2010 to 2020. Patients aged ≥ 65 years who were diagnosed with MCI were included and categorized based on their dental implant status. Cox proportional hazard regression models were used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for the incidence of Alzheimer’s disease (AD) and dementia with Lewy bodies (DLB). The models were adjusted for age, sex, Charlson comorbidity index scores, income level, and residential area. Results: Among 63,901 patients with MCI, those who received dental implants (n = 9,203) showed a significantly lower risk of developing AD than those without implants (n = 54,698) (adjusted HR = 0.37, 95% CI = [0.346–0.388], p < 0.001). For DLB, the association was not statistically significant after adjusting for confounders (adjusted HR = 0.57, 95% CI [0.326–1.004], p = 0.05). Patients with MCI who received dental implants were generally younger, with a higher proportion of males, urban residents, and individuals in higher income brackets. Conclusions: Although additional residual confounding factors cannot be excluded, dental implantation in patients with MCI was consistently associated with a lower risk of progression to AD after adjustment for measured covariates. Further prospective and interventional studies are warranted to explore the underlying mechanisms and establish a more apparent causal relationship between oral health and dementia risk.