The cariostatic properties of sealants are attributed to the physical obstruction of the pits and fissures. This prevents the penetration of fermentable carbohydrates and so the remaining bacteria cannot produce acid in cariogenic concentrations. Dental sealants are cost effective treatment modalities when placed on teeth of children at high risk for dental caries. The fact that pits and fissure sealants are safe and effective should justify their routine use as a preventive measure.