The association between dental caries, periodontal diseases, and tooth loss with diabetes mellitus among the elderly population

Purpose Our study investigated the association between dental caries, periodontal diseases, and tooth loss with diabetes mellitus (DM) among the elderly population, representing the first study of its kind in Iran. Methods This was a cross-sectional community-based study as a part of the second wave of the Birjand longitudinal aging study (BLAS, 2021–2022) for people older than 60. We used the Comprehensive Geriatric Oral Health Assessment Tool (CGOHAT) for the oral health evaluation. Participants were initially categorized into diabetic and non-diabetic groups. Those patients with DM were further categorised into uncontrolled and controlled diabetes based on their HbA1c level. The association between periodontitis, gingivitis, and edentulism with type II diabetes mellitus and uncontrolled diabetes was assessed using logistic regression. Results Among the 1,011 participants, 324 (32.04%) had DM. The mean ± SD DMFT was 27.06 ± 7.71 and 27.07 ± 7.72 among those with and without DM, respectively ( p = 0.976 ). The M index comprised 85.46% of the total DMFT among those without DM and 84.51% among those with DM. The prevalence of periodontitis was higher among those without DM (110, 32.84%, p = 0.390 ). The prevalence of gingivitis was higher among those with DM (73, 45.06%, p = 0.617 ). Among the diabetic group, 137 (42.28%) had controlled DM. Based on the adjusted matched multivariate logistic model, decayed teeth (1.24, 95%CI: 1.06 – 1.46, p-value = 0.006 ), periodontitis (2.78, 95%CI: 1.02 – 7.56, p-value = 0.044 ), and moderate tooth loss (5.73, 95%CI: 1.13 – 28.88, p-value = 0.034 ) were significantly associated with increased odds of uncontrolled DM. Conclusions Based on the findings of this study, tooth loss was highly prevalent among the elderly Iranians regardless of their diabetes status. Also, periodontitis, tooth loss, and decayed teeth were significantly associated with increased odds of poor glycemic control among those with DM. Thus, it can be concluded that improving the oral health of the geriatric population may be a crucial part of improving the glycemic control among those with diabetes which has been frequently neglected.