Biochemical composition of the saliva and dental biofilm of children with Down syndrome.

Background The biochemical composition of the saliva and biofilm of children with Down syndrome (DS) may be associated with the incidence of caries in this population. Aim To evaluate the biochemical composition of the saliva and dental biofilm of children with DS in the city of Porto Alegre, RS. Design The sample comprised 144 children between 6 and 14 years of age, of whom 61 had DS and 83 did not. Stimulated saliva samples were collected from all participants, as were samples of 48-h biofilm. Fluoride (F), calcium (Ca), and phosphorus (Pi) concentrations in saliva and biofilm were determined by colorimetric method (Ca and Pi) or selective electrode (F). The level of insoluble extracellular polysaccharide (EPS) in dental biofilm was measured using sulphuric acid method. Results Salivary concentration of F, Ca, and Pi did not differ between children with and without DS. The dental biofilm of children with DS, however, showed higher Pi and EPS levels than that of children without the syndrome (P < 0.05). Conclusions The present results suggest that despite the salivary composition being similar between groups, the dental biofilm of children with DS has higher cariogenic potential than that of children without this condition.