Association between socioeconomic status and dental caries among Chinese preschool children: a cross-sectional national study

ObjectivesSocioeconomic inequalities in oral health are often neglected in oral health promotion. This cross-sectional study assessed the association between dental caries and socioeconomic status (SES) among preschool children in China.DesignCross-sectional study.SettingData from the Fourth National Oral Health Survey of China (2015), comprising of 40 360 children aged 3–5 years was used.MethodsDental caries indicators including prevalence of dental caries, dental pain experience and number of decayed, missing and filling teeth (dmft). SES indicators included parental education and household income. The associations between SES and dental caries were analysed by using negative binomial regression or Poisson regression models according to data distribution. Relative and absolute inequalities in dental caries were quantified by using the Relative Index of Inequality (RII) and Slope Index of Inequality (SII), respectively.ResultsThere were significant associations between SES and prevalence of dental caries and dmft (p