RESUMEN
Different clinical steps, weak and ineffective bond are some of the problems of using fissure sealant in primary teeth. The aim of this study was to compare the effect of a total-etching adhesive [single bond] and a self-etching adhesive [G bond] on the shear bond strength [SBS] of a light curing pit and fissure sealant with primary enamel. In this experimental study, the crowns of 10 caries-free primary molars were sectioned in a bucco-lingual direction. These 20 specimens were randomly assigned into two groups [single bond and G bond]. A light curing pit and fissure sealant [Concise] was bonded to the enamel following application of each bonding system. After 24 hours, the shear bond strength was measured. The data were statistically analyzed using t-test. The failure mode was determined in a stereo microscope atx20. The shear bond strength of single bond [16.71 +/- 0.72] was higher than the G bond [9.62 +/- 1.4]. There was a significant difference between the shear bond strength in two groups [p<0.05]. Most failures were cohesive [80% in single bond and 90% in G bond]. According to our data, the self-etching adhesives [G bond] are not reliable alternatives to the total-etching adhesives, if strong bond strength is needed