The relationship between levels of secretory IgA and incidence of dental caries has been the object of controversial studies. Selective IgA deficiency (SIgAD) is the commonest primary immunodeficiency and may be found in apparently healthy individuals but is also associated with a variety of diseases. In the present study the authors evaluated the prevalence [correction of incidence] of caries by means of caries indexes in a group of children with severe and partial SIgAD and in a group of children age-matched healthy control. Evaluated caries indexes were significantly higher in children with severe SIgAD as compared to control groups.