The presence of dental enamel defects in coeliac disease and their relation to hypocalcaemia or a particular HLA class in 82 Italian children with coeliac disease was studied. Demarcated opacities or hypoplasia were detected in 23 subjects (group 1) while minimal or no dental lesions were found in the remaining 59 patients (group 2); in 189 normal controls, enamel lesions were significantly less frequent than in patients with coeliac disease (14.8% versus 28.0%; p < 0.005). No statistically significant differences were found for age at diagnosis and calcium concentrations between groups 1 and 2. Regression analysis showed a correlation between age at diagnosis and number of teeth with enamel defects. In our patients, the presence of HLA DR3 antigen significantly increased the risk of dental lesions, while genotype DR5,7 seemed to protect against enamel defects. A logistic regression analysis of the variables age, serum calcium concentrations, number of affected teeth, type of enamel defect and DR antigens showed that only DR antigens discriminated coeliac disease patients with from those without enamel defects.