Nicolau B, Marcenes W et al. Caries Res 2003; 37: 319–326

Like other chronic diseases, caries has a behavioural dimension which may be affected by socio-economic factors. The first phase of this study invited participation of all 13-year-old children in a Brazilian town; 85% did so, and were examined and interviewed. In the second phase, 330 families of these children were randomly selected, and 94% participated. There were further exclusions because of incomplete data availability.

Mean DMFT was 4 in phase I and 3.8 in phase II. In phase II, 3/4 of children were from 2 parent families and 7% had a step-parent; 2/3 of families had incomes below 5 times the Brazilian minimum wage. More than 3/5 of the adolescents had been born in brick houses, nearly 2/5 were first children, and 12% were of low birth weight.

Regression analysis showed high caries levels were most related to house material at birth, not being the first child, and low birth weight. The authors discuss the concept of 'biological programming' in relation to how these factors might affect caries.