History of malaria and tooth loss in a malaria-endemic population of the Brazilian Amazon: a cross-sectional study

Objective To evaluate the association between self-reported history of malaria and tooth loss in a malaria-endemic population of the Brazilian Amazon. Methods This cross-sectional study included 290 individuals from urban and rural areas of Monte Negro and the riverside community of Calama (Rondônia, Brazil), recruited during university-led humanitarian expeditions in 2018–2019. Tooth loss was clinically assessed using the Caries Assessment Spectrum and Treatment (CAST) instrument. An ordinal outcome was constructed based on the number of missing teeth (0, 1–9, 10–19, and ≥ 20 teeth). The main exposure was self-reported history of malaria infection. Associations were examined using ordered logistic regression models, with results expressed as odds ratios (OR), 95% confidence intervals (CI), and p-values. Multivariable models were adjusted for age, educational attainment, and sanitation conditions. Results Overall, 76.6% of participants (95% CI: 71.3–81.1) had lost at least one tooth, 25.5% (95% CI: 20.8–30.9) had lost ≥ 10 teeth, and 8.3% (95% CI: 5.6–12.1) had lost ≥ 20 teeth. Half of the sample (50.0%; 95% CI: 44.3–55.8) reported a history of malaria. In adjusted analyses, malaria history was associated with higher odds of more severe tooth loss (OR = 1.97; 95% CI: 1.13–3.43; p = 0.017). Age showed a strong gradient, with significantly higher odds of tooth loss severity across older age groups ( p < 0.001). Conclusions In this malaria-endemic population, a history of malaria was associated with greater tooth loss severity. Although age remained the strongest determinant, malaria history may represent an indicator of increased risk for poor long-term oral health outcomes in endemic populations. These findings highlight the importance of integrating oral health into broader public health strategies in malaria-endemic settings.