Methods: A total of 44 extracted human single-rooted teeth were randomly divided in four groups and restored using WhitepostDC glasss-fiber posts (FGM, Joinville, SC, Brazil) and following luting agents: All Bond SE/Duo-Link (ABSE) (Bisco, Inc, Schaumburg, IL, USA), All Bond 3/Duo-Link (AB3) (Bisco, Inc, Schaumburg, IL, USA), BisCem (BC) (Bisco, Inc, Schaumburg, IL, USA), Clearfil ED primer II/Clearfil Esthetic Cement (CLF) (Kuraray Medical Inc, Okayama, Japan). One week after luting procedures, the samples were thermocycled in water (1000×, 5/55 °C, dwelling time of 30 s), and then embedded in acrylic resin. Three sections (cervical, middle and apical) of 2 mm thickness were prepared from each specimen, and each section was subjected to the push-out test method. One additional specimen for each group was prepared for scanning electron microscopy analysis. The data were calculated and analyzed using the Kolmogorov-Smirnov test, two-way ANOVA, one-way ANOVA, and the Scheffe test. Significance was set at p < 0.05. Results: The push-out bond strength values for BC and ABSE (13.50±2.24 MPa, 12.42±2.35 MPa, respectively) were not significantly different (p > 0.05), but were both significantly higher than the means for AB3 and CLF (10.22±2.23 MPa, 9.08±1.96 MPa, respectively) (p < 0.001). There were significant differences in bond strength among root thirds, with a reduction in values from the cervical to apical third (p < 0.05).
Conclusion: Adhesive luting systems with different chemical formulations and applications yielded significantly different bond strengths to different regions in root dentin.