sealant microleakage after using nano-filled bonding agents on saliva-contaminated enamel.

the efficacy of correctly applied fissure sealants has been revealed in the prevention of caries. saliva and moisture contamination of the etched enamel surface before sealant placement can decrease the bonding strength of the sealant to the enamel. the aim of this study was to test the new bonding agents containing nano-fillers in order to reduce the negative effect of saliva contamination on the sealant micro leakage.seventy five sound human premolars were randomly assigned to five equal groups as follows: group a: etching, sealant; group b: etching, saliva contamination, sealant; group c: etching, saliva contamination, single bond, sealant; group d: etching, saliva contamination, adper single bond 2, sealant; group e: etching, saliva contamination, n bond, sealant. the samples were thermo-cycled and immersed in basic fuchsine 0.5% by weight. then, the teeth were sectioned bucco-lingually and parallel to the long axis into two segments. finally, the length of dye penetration at the sealant-tooth interface was scored according to a four-point scale.micro-leakage was higher in group b compared to the other groups, while there were no differences among the evaluated dentin adhesives.the use of nano-filled bonding agents as an intermediate layer between the etched enamel and the sealant can reduce sealant micro-leakage after saliva contamination at the level of the uncontaminated enamel.