Individual and contextual factors associated with tooth loss in adolescents in the Midwest region of Brazil

To analyze factors associated with tooth loss in 12-year-old adolescents, data were collected from 615 adolescents attending public schools in the five most densely populated cities in the state of Mato Grosso do Sul, Brazil. Tooth loss was assessed using the M component of the DMFT index. Information was also obtained on access to fluoridated water, consumption of unhealthy foods, and sedentary behaviour. Guided by the social determinants of health framework, multilevel logistic regression analyses were conducted to test associations. The prevalence of tooth loss among adolescents was 5%. In the adjusted models, sedentary behaviour was significantly associated with tooth loss [odds ratio (OR) = 1.77; 95% CI: 1.28-2.45], while access to fluoridated water was a protective factor [OR = 0.40; 95% CI: 0.16-0.99]. Household income below the poverty line and moderate to high consumption of unhealthy foods showed higher odds of tooth loss, but the confidence intervals included the null value in the adjusted model. Sedentary behaviour was significantly associated with tooth loss in 12-year-old adolescents, whereas access to fluoridated water was protective. Sedentary behaviour should be interpreted as a marker of broader lifestyle and social vulnerabilities rather than as a direct causal factor.