RESUMEN
Abstract Objective: To assess the incidence of caries in a two-year period among low birth weight (LBW), very low birth weight (VLBW), and extremely low birth weight (ELBW) children considering socioeconomic indicators, dietary factors and oral hygiene. Material and Methods: A convenience sample was formed of 42 low birth weight children aged two to five years at baseline. Two examiners diagnosed caries using the World Health Organization criteria. Birth weight, socioeconomic indicators and diet were collected from medical records and questionnaires. Binomial models were used to estimate unadjusted and adjusted rate ratios (RR) and respective 95% confidence intervals for the factors evaluated. Results: Thirty-six children were re-examined after two years. The incidence of dental caries was 36.7%. The dmft index was 0.44 (±1.25) at baseline and increased to 1.36 (±3.85) at follow-up. VLBW children (1,000 to 1,500 g) (RR=0.23; 95%CI: 0.08-0.72) and LBW children (1,500 to 2,500 g) (RR=0.06; 0.01-0.55) had fewer carious lesions compared to ELBW children (<1,000 g). Carious lesions were more frequent among children with a lower income (RR=6.05; 1.05-34.84) and less frequent among those who did not consume sweetened juice, tea or yogurt (RR: 0.21; 0.07-0.62). Conclusion: An inverse dose-response relation was found between birth weight and the incidence of caries. A lower income and the consumption of sweetened beverages were risk factors for the development of caries (AU).