Material and Method: The subjects included 111 children (57 boys and 54 girls), aged 11 and 12 years, who were studying in grades 4 to 6 in the year 2011. The data were collected through questionnaires, interview, and oral examination. Results were obtained by means of descriptive, bivariate, and multiple logistic regression analyses.

Results: Prevalence of dental caries in the children was 82.9% with the mean DMFT of 2.28. The dental caries prevalence in permanent and primary dentitions was 69.4% and 34.2%, respectively. About 10.2% of the children were underweight, 13.0% were obese, and 7.5% were stunting. Findings from the final multiple logistic regression models showed that weight-for-age malnutrition as well as eating sweets before bedtime were significantly related to dental caries in primary dentition, with the adjusted odds ratio (95% CI) being 6.68 (1.57, 28.41) and 5.34 (1.60, 17.77), respectively. Family income was significantly related to permanent dental caries with the odds ratio (95% CI) being 9.60 (1.89, 48.59).

Conclusion: Nutritional status is associated with dental caries among these elementary schoolchildren. Larger studies extending to cover other elementary schools in Na Klang district should be conducted so that the results will be representative of all elementary schools in Na Klang district, Nongbua Lampoo province.

Keywords: Dental caries, Nutritional status, Schoolchildren, Thailand