Oral health inequalities in Italian schoolchildren

Objective: To evaluate which of indicators of socio-economic status (SES) has the strongest association with caries status in a 6-years-old population: the educational level of each parent (individual-level); the mean price of housing/m2 in the area where the family resides; or the mean per capita income in the area where the family lives (area-level). Method: The study was carried out in Sassari and in nine small surrounding towns. Caries was recorded in 2,040 schoolchildren using decayed/missed/filled surface index at d3 level in primary dentition. Parents filled in a standardized questionnaire regarding nationality, level of education, frequency of dental check-up, child’s previous experience to dentist, perception of child’s oral health and child’s oral hygiene habits. In data analysis, Sassari was considered an urban area, while the mean income of the nine surrounding towns was considered typical of a non-urban area. A multilevel mixed Poisson regression and a multinomial logistic regression were performed to determine which SES indicator, at individual- or at area-level, fits better with caries disease. Result: At the individual-level of SES, mothers’ educational level was associated with their children’s caries severity (χ2(9)=147.51 p<0.01): as educational level rose, the proportion of children with high numbers of carious lesions fell. The two income indicators (area-level SES) were not associated. Mothers’ perception of child’s oral health was the only covariate that was always associated in each caries severity stratum and for all levels of mothers’ education. The frequency of child dental check-up, namely the presence of tooth pain, was statistically associated with the highest caries figures in two levels of mothers’ education: compulsory and secondary. Conclusion: Individual-level indicator of SES, mother’s educational level, is a useful SES measure of caries in children in a low-income population; meanwhile area-level income indicators have not proved useful when economic disparities in the population are quite reduced.