Objective: To determine whether periodontal status is associated with oral function, including masticatory performance and occlusal force, among community-dwelling older adults.

Background: Although a potential association between periodontal status and oral function has been reported, variations in the root surface area (RSA) of each tooth have not been considered.

Methods: We used data from a population-based study involving community-dwelling older adults. The RSA with periodontal ligament (RSA-PL), which quantifies the RSA attached to the periodontal ligament and alveolar bone, was calculated based on full-mouth periodontal examination. Masticatory performance was assessed using spectrophotometric measurement of the color (a* value) of color-changing chewing gum. The bilateral maximal occlusal force (MOF) was measured using a pressure-sensitive sheet and dedicated software. The associations of the RSA-PL, a quantitative marker of periodontal tissue support, with the a* value and MOF were assessed using linear regression models.

Results: The analyses included data from 250 adults [60.8% women; age, mean (standard deviation) 82.5 (5.0) years]. On average, the study participants had an RSA-PL of 26.3 cm² , a* value of 25.0, and an MOF value of 555.1 N. After adjustments for potential confounders, including dentition status, age, sex, dental visit regularity, smoking status, physical activity level, depressive symptoms, a history of stroke or diabetes mellitus, and body mass index, the RSA-PL was found to be associated with the a* value [coefficient (per 1 cm² increase): 0.16, 95% confidence interval (CI) 0.10-0.22)] and MOF (coefficient: 9.2, 95% CI 5.3-13.1).

Conclusion: This study demonstrated that greater amounts of remaining tooth-supporting structures, indicated by higher RSA-PL values, were associated with better masticatory performance and a higher occlusal force among community-dwelling older adults.

Keywords: aged; bite force; epidemiology; mastication; periodontal diseases.

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