A cross-sectional study on the association between vitamin D levels and caries in the permanent dentition of Korean children

Background: A recent study in Canada reported that vitamin D deficiency is associated with dental caries. Because Koreans have been reported to be deficient in vitamin D, we investigated the relationship between dental caries and reduced serum vitamin D levels in Korean children. The purpose of this study was to analyze the relationships between blood vitamin D [25(OH) D] concentrations and dental caries in the permanent dentition of Korean children. Methods: Data were collected from the Korea National Health and Nutrition Examination Survey performed in 2008-2013. A total of 1688 children (10-12 years of age) were enrolled. Vitamin D intake was measured through analysis of 25-hydroxy vitamin D [25(OH) D] levels. Caries experience in permanent dentition was assessed using the decay-missing-filled teeth (DMFT) index and decayed-missing-filled (DMF) rate. Statistical analyses included complex samples Chi-square tests, complex samples logistic regression analyses, and Pearson's correlations. Results: The group with 25(OH) D levels lower than 50 nmol/L had a higher proportion of children with caries in the permanent dentition and permanent first molar than the group with 25(OH) D levels of 50 nmol/L or more. When external factors, such as sex, were controlled, 25(OH) D levels were not significantly correlated with caries, but were significantly correlated with first molar caries. Children with 25(OH) D levels lower than 50 nmol/L were 1.295 times more likely to have first molar caries than those with 25(OH) D levels of 50 nmol/L or more. Additionally, 25(OH) D levels and DMFT were negatively correlated; however, the degree of correlation was not strong. Conclusions: The association between 25(OH) D and dental caries is still not clear. However, our findings suggested that vitamin D insufficiency may be a risk factor for dental caries.