Association of Oral Health Literacy and School Factors with Untreated Dental Caries among 12-Year-Olds: A Multilevel Approach.

Dental caries are a global health problem that affects all age groups and must be considered a public health priority due to its significant financial costs and impact on the quality of life. This study evaluated the association between oral health literacy (OHL), school factors, and untreated dental caries in 12-year-old Brazilian adolescents using a multilevel approach. A population-based cross-sectional study was carried out with 740 adolescents randomly selected from private and public schools in Campina Grande, Brazil. Two dentists were trained and calibrated to diagnose dental caries using the Nyvad index and OHL using the Brazilian Rapid Estimate of Literacy in Dentistry (BREALD-30). The caregivers of the adolescents reported demographic data (sex, skin color, and socioeconomic status). Data of school factors such as the type of school and the school grade retention rate were classified through a 2-step hierarchical cluster analysis to obtain the school environment. A robust multilevel log-linear negative binomial regression for complex samples was performed (p < 0.05). In the analysis, adjusted by individual determinants, nonwhite skin color (RR = 2.20; 95% CI 1.56-3.12), a low socioeconomic status (RR = 1.60; 95% CI 1.09-2.34), a low OHL score (RR = 0.94; 95% CI 0.91-0.98), and low satisfaction with the last dental appointment (RR = 2.25; 95% CI 1.67-3.04) were associated with untreated dental caries. The following factors remained associated with untreated dental caries in the final model: students from an unfavorable learning environment (RR = 2.20; 95% CI 1.27-3.80), nonwhite skin color (RR = 1.92; 95% CI 1.27-2.91), a low socioeconomic status (RR = 1.82; 95% CI 1.12-2.94), a low OHL score (RR = 0.95; 95% CI 0.91-0.98), and low satisfaction with the last dental appointment (RR = 2.07; 95% CI 1.47-2.91). Untreated dental caries in early adolescence were impacted by the school environment, the socioeconomic status, OHL, and the adolescent's satisfaction with the last dental appointment.