Secular trends in dental caries in Korean children and adolescents: 2007-2019 Korea National Health and Nutritional Examination Survey

Abstract

Dental caries is a common preventable childhood disease that has negative effects on physical, psychological, and social well-being. The present study was conducted to examine the secular trends in the prevalence of dental caries among Korean children and adolescents over time through subgroup analysis based on age, sex, abdominal obesity, obesity, and metabolic syndrome (MetS). This serial cross-sectional study utilized representative data from the Korea National Health and Nutritional Examination Survey, covering the period from 2007 to 2019. The study participants included 9,702 children and adolescents aged between 10 and 18 years. A linear-by-linear association test was performed to evaluate the secular trend of dental caries according to the subgroups. The mean prevalence of dental caries significantly decreased in both boys and girls during the study period (all p-values for trend < 0.001). These trends were consistent across different age subgroups: 10-12, 13-15, and 16-18 years. In subgroup analysis, the prevalence of dental caries significantly decreased in normal-weight boys and girls (all p-values for trend < 0.001). However, no significant decrease was observed in the overweight or obese groups for either sex. Importantly, the prevalence of dental caries did not decrease significantly in subgroups with abdominal obesity or MetS. In the non-abdominal obesity group, both boys and girls showed a significant decrease in dental caries prevalence (all p-values for trend < 0.001), while in the abdominal obesity group, a significant decrease was observed only in boys (p-value for trend = 0.027). No significant decrease was observed in the abdominal obesity group for girls. Similarly, in the non-MetS group, both boys and girls showed a significant decrease in dental caries prevalence (all p-values for trend < 0.001), while no significant decrease was observed in the MetS group for both sexes. The prevalence of dental caries has significantly decreased over the past 13 years among Korean children and adolescents. However, in subgroups with obesity or overweight, abdominal obesity, and MetS, no decrease was observed in the prevalence of dental caries.