RESUMO
Abstract Caries disease can lead to strong impact in terms of pain and suffering, to functional impairment, and to negative effects on quality of life. Studies have demonstrated that the impact on quality of life increases with dental caries severity, and few studies have assessed the relationship between caries activity and children's oral health-related quality of life (OHRQoL). This cross-sectional study aimed to assess the impact of dental caries severity and activity on the OHRQoL of schoolchildren. The study was conducted with a sample of children aged 8 to 11 years from Pelotas, southern Brazil. Children answered the Child Perceptions Questionnaire 8-10, and socioeconomic data were collected. Children's dental caries (Kappa value of 0.95), PUFA, traumatic dental injuries, and malocclusion were examined. The Mann-Whitney, Kruskal-Wallis, and Poisson regression tests were performed. A total of 119 children were included. Children with initial (mean ratio (MR) of 1.92; 95% confidence interval (95% CI) of 1.05-3.48), moderate (MR: 2.66; 95%CI: 1.44-4.90), and severe carious lesions (MR: 2.65; 95%CI: 1.46-4.79) had a greater impact on OHRQoL compared with those without carious lesions (p =0 .047). Children with active carious lesions exhibited a greater impact on OHRQoL (MR:1.53 and 95%CI: 1.11-2.11) when compared to those without active lesions (p = 0.019). The findings demonstrate an association between dental caries severity and activity and the OHRQoL of school-aged children.