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Updated: Oct 11, 2025

Oral Health Assessment by Lay Personnel for Older Adults
Published on: February 2, 2020
Association between number of remaining teeth and healthy aging in Japanese older people: The Ohsaki Cohort 2006
Sanae Matsuyama1, Yukai Lu1, Jun Aida2
1Division of Epidemiology, Department of Health Informatics and Public Health, School of Public Health, Tohoku University Graduate School of Medicine, Sendai, Japan.
Aim:
Maintaining ≥20 teeth is a public health goal worldwide. Healthy aging, which includes psychological and social well-being, as well as physical indicators, has attracted a great deal of attention with the progression of aging societies. However, no studies have examined the association between the number of remaining teeth and healthy aging. This study aimed to investigate the association between the number of remaining teeth and healthy aging.
Methods:
This community-based longitudinal cohort study included 8300 Japanese people aged ≥65 years who were free of disability and depression in the baseline survey in 2006. The participants were categorized into four groups according to the number of remaining teeth at baseline: 0-9, 10-19, 20-24 and ≥25. The primary outcome was healthy aging (defined as meeting all four of the following criteria: free of disability, free of depression, high health-related quality of life and high life satisfaction), as assessed by a questionnaire survey carried out in 2017. Multiple logistic regression was used to calculate the corresponding odds ratios and 95% confidence intervals.
Results:
During about 11 years of follow-up, 621 (7.5%) participants attained healthy aging. Participants with ≥20 remaining teeth showed a higher healthy aging rate. Compared with participants with 0-9 teeth, the multivariate-adjusted odds ratios (95% confidence intervals) for 10-19, 20-24 and ≥25 teeth were 0.98 (0.77-1.26), 1.28 (1.01-1.63) and 1.59 (1.24-2.03), respectively.
Conclusions:
These findings suggest that maintaining ≥20 teeth was associated with healthy aging. Geriatr Gerontol Int 2022; 22: 68-74.
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