Objectives: The aim of this in vitro study was to compare the microtensile bond strength (μTBS) of single versus two layers of three different 7th generation adhesives.
Materials and Methods: One third of the human molar teeth from the coronal portion was removed and smear layer was created on these surfaces by using Silicone carbide paper. Adper Easy Bond (AEB), ClearfilS3 bond Single Dose (CS3) and Optibond Unidose (OB) were applied to flat dentin according to the manufacturer’s instructions. Six groups; Group1: single application of AEB, Group2: twice application of AEB Group3: single application of CS3, Group4: twice application of CS3 Bond Group5: single application of OB, Group6: twice application of OB, were obtained. After applying adhesive, resin composite crowns were build up in 1mm increments up to 5 mm. After storage in distillated water for 24 hour (h), the specimens were sectioned to sticks and 15 sticks were obtained for each group. The sticks were stressed in tension until failure to see the microtensile bond strength values using a microtensile testing machine and the data were recorded. After recording data in SPSS 15.0, statistical analyses were made with ANOVA, Independent Sample T test and Tukey’s post-hoc test at 0.05 level of significance.
Results: Significant differences were not found among the G1, G3, G5 (p>0.05). G6 exhibited significantly higher μTBS compared to the G2 and G4 (p<0.001). No significant differences were found among the groups regarding the failure types between cohesive or adhesive (p>0.05). Lower μTBS values were observed in two layer application when compared to the one layer application of AEB and CS3. G6 resulted in significantly higher μTBS values compared to G5 (p<0.001).
Conclusion: The results of the current investigation showed that two layer applications would be beneficial depending on the composition of adhesive and dentin substrate.
Published on: Jan 10, 2015 Pages: 1-4