the effect of dental adhesive composition and etching mode on microleakage of bonding agents in primary molar teeth

Statement of the problem: the dilemma of microleakage at the composite-tooth interface is still a major challenge in operative dental practice. purpose: this study aimed to compare the microleakage of universal adhesive with self-etch and total-etch bonding strategies for restoration of class-ii primary molar cavities. materials and method: this in vitro, experimental study was conducted on 75 extracted primary molars. class-ii cavities were prepared in mesial or distal surfaces. the teeth were randomly divided into five groups of adper single bond 2 (3m espe; st paul, mn, usa), clearfil se bond (kuraray noritake, osaka, japan), g-bond (gc corp., tokyo, japan), g-premio bond (gc corp., tokyo, japan) with total-etch mode and g-premio bond with self-etch mode. cavities were also restored with nano-hybrid resin composite (grandio, voco, cuxhaven, germany) and incubated for 24 hours, followed by thermo-cycling at 1500× between 5-55°c within a dwell time of 20 seconds. later, the cavities were placed in 1m silver nitrate solution and evaluated under a stereomicroscope. finally, microleakage was assessed quantitatively and qualitatively. one tooth in each group was prepared and evaluated under a scanning electron microscope (sem). data were analyzed using one-way anova, tukey's post hoc test and chi-square test (p< 0.05). results: the microleakage values were significantly different in the study groups (p< 0.05). the highest level of microleakage was noted in g-bond and the lowest in g-premio bond with total etching. there was a significant correlation between the qualitative and quantitative measurements of microleakage. conclusion: the g-premio bond yielded acceptable results in terms of microleakage in total-etch and self-etch modes. however, additional etching is recommended to improve the quality of bonding