Association of Nutritional Status and Oral <i>Veillonella</i> With Caries Status in Preschool Children in Manitoba.

<b>Purpose:</b> To gain a greater understanding of the relationship between oral Veillonella, nutrition, and early childhood caries (ECC). <b>Methods:</b> A case-control design was used. A total of 158 children (83 with ECC, 75 caries-free) were recruited in Winnipeg, Manitoba, Canada, from March 2019 to November 2020. Nutritional profiles were determined using NutriSTEP^® (Nutrition Screening Tool for Every Preschooler and Toddler). Bacterial presence was assessed using relative abundance data from 16S rRNA gene amplicon sequencing of plaque samples. A multivariable logistic regression model was used to estimate the association of ECC with NutriSTEP^® scores and oral Veillonella. <b>Results:</b> Caries-affected children tended to be older, Indigenous, and established residents, have less-educated parents (parents/caregivers), and live in rural/remote areas (P<0.05). Caries-affected children had higher total NutriSTEP^® scores than caries-free children (23.7±6.8 versus 21.1±6.6; P=0.008). Caries-affected children ate fewer vegetables, consumed more fast food, and ate too little/too much during the day (P<0.05). Children with abundant Veillonella dispar (odds ratio [OR] equals 4.21, 95 percent confidence interval [95% CI] equals 2.03 to 8.74) and Veillonella parvula (OR equals 2.33, 95% CI equals 1.10 to 4.91) with higher NutriSTEP^® scores (OR equals 1.04, 95% CI equals 0.99 to 1.10; and OR equals 1.08, 95% CI equals 1.02 to 1.14, respectively) were more likely to have ECC. <b>Conclusions:</b> The findings reflect the importance of V. dispar and V. parvula for dental caries and support a tentative association between oral Veillonella, nutrition, and early childhood caries. Children with abundant Veillonella and greater nutritional risk may be more susceptible to ECC.