Determinants of Dental Caries in Infants
Objectives: The origins of early childhood caries (ECC) begin prenatally, before teeth arrive. Maternal vitamin D status during pregnancy may affect calcification of the developing dentition, and subsequently predispose children to developmental defects of enamel ECC. This study was conducted in order to determine whether a relationship exists between prenatal maternal vitamin D status (via a cord blood sample) and caries prevalence in offspring. Factors predisposing children to ECC were also explored. Methods: A prospective cohort of expectant mothers was selected from a high-risk urban population seeking prenatal care in Winnipeg, Canada. Participants were recruited into one of two groups; an intervention group and control group. The intervention group received two doses of 50,000 IU of vitamin D, one in the second trimester and one in the third trimester. A prenatal questionnaire was completed at the first visit. Cord blood was taken at birth and analysed for 25(OH)D. Participants returned at the time of their child's first birthday, where a follow up questionnaire and dental exam of the child were completed. The dental examiner was blinded to the vitamin D cord level. A p value ≤ 0.05 was significant. Results: 283 women were recruited (mean age 23.4 ± 5.6 years); 141 women were in the supplementation group, while 142 served as controls. Cord blood was drawn from 107 women in the intervention group and 109 controls. The mean 25(OH)D level was 49.6 ± 24.3 nmol/L. 175 women returned for the infant follow-up visit. The mean age of the children was 19.7 ± 8.1 months and 52% were male. Overall, 26.3% of children had ECC, and the mean decayed tooth (dt) score was 0.94 ± 2.16 teeth (range 0-16). There was no significant difference in prevalence of children with ECC between the intervention and control group (p=0.21). The 25(OH)D status 3 also did not significantly impact ECC (p=0.54). However, it was determined that mothers with higher cord 25(OH)D levels had infants with significantly lower dt scores (p=0.0011). Factors associated with ECC included, receiving government assistance (p=0.011), household income below $28 000 (p=0.0024), unemployment (p=0.00019), presence of enamel hypoplasia (p=0.0063) and developmental defects of enamel (p=0.0086), longer duration of being bottle-fed (p=0.0079) and age (p<0.0001). Conclusion: The vitamin D dose used in this study did not significantly increase the cord blood vitamin D status compared to the control group. No relationship was found to exist between the two groups and prevalence of ECC. However, significance was seen in an inverse relationship between 25(OH)D levels and the number of decayed primary teeth. Similarly designed studies, with an altered vitamin D regimen, need to be conducted in order to receive more conclusive results.