Effect of income trajectory on dental service utilization patterns during the transition from childhood to adolescence: a 10-year cohort study

OBJECTIVES: This study aimed to investigate the influence of income trajectories on dental service utilization patterns during the transition from childhood to adolescence in a Southern Brazilian birth cohort. MATERIALS AND METHODS: Children were followed over 13 years (T1, T2, and T3). Income trajectories (stable low/decreasing vs. stable high/increasing) were identified using group-based trajectory modeling based on finite mixture models. Outcomes included frequency of dental visits and reason for the last visit (preventive vs. curative). Socioeconomic disparities were explored using the non-linear Blinder-Oaxaca decomposition method. RESULTS: From 639 children at baseline (T1), 449 were followed at T2 and 429 at T3 (67.1% retention). Adolescents from stable high or increasing-income trajectories had a lower prevalence of dental visits for curative reasons (OR = 0.29; 95% CI 0.09-0.90). Decomposition analysis showed that maternal education (9%) and skin color (12.5%) explained only a small portion of these inequalities, suggesting an independent effect of income over time. CONCLUSIONS: Individuals with increasing income were less likely to use dental services for curative purposes, regardless of race, dental caries, and maternal education, highlighting the impact of economic stability on oral health behaviors. CLINICAL RELEVANCE: Income trajectories over time influence the pattern of dental service utilization in adolescence. Identifying individuals in disadvantaged socioeconomic trajectories may support targeted preventive strategies and improve access to care.