Background: The study was aimed to describe caries prevalence and severity and health inequalities among Italian preschool children with European and non-European background and to explore the potential presence of a social gradient.
Methods: The ICDAS (International Caries Detection and Assessment System) was recorded at school on 6,825 children (52.76% females). Caries frequency and severity was expressed as a proportion, recording the most severe ICDAS score observed. Socioeconomic status (SES) and behavioral habits of children/parents/caregivers were estimated by mean a standardized self-submitted questionnaire filled-in by parents. The Slope Index of Inequality (SII) based on regression of the mid-point value of caries experiences score for each SES group was calculated and a social gradient was generated as the weighted sum of the worst circumstances deriving from social explanatory variables. Children were stratified into four social gradient levels based on the number of worst options. Multivariate regression models (Zero-Inflated Negative Binomial logistic regression in children with European background and a logistic regression in children with non-European background) were used to elucidate the associations between all explanatory variables and health outcome (namely the caries prevalence). Mantel Haenszel trend of odds adjusted by immigrant background and area of living were calculated to study the existence, dimensions and direction of a social gradient in oral health.
Results: Overall, 54.37% (95%CI 46.71–58.28%) of the children were caries-free; caries prevalence was statistically significant higher in children with non-European background compared to European children (72.59% vs 41.62% p<0.01). A statistically significant trend was observed for ICDAS 5/6 score and the worst social/behavioral level (Z=5.24, p<0.01).
Conclusions: Data show how caries in preschool children is an unsolved public health problem especially in those with a non-European background. The proposed gradient was clearly able to identify children with the worst dental conditions.