Push-out bond strength and SEM analysis of two self-adhesive resin cements: An in vitro study

PurposeThe retentive strength of two self-adhesive resin cements used for the cementation of fiber posts into root canals filled with methacrylate-based sealer and core material (Resilon) was evaluated using the thin-slices push-out test on human molars.Materials and methodsRelyX Fiber Posts #3 (3M ESPE, Seefeld, Germany) were luted with RelyX U200 (3M ESPE) (n = 10) and Maxcem Elite (Kerr Corporation, Orange, CA, USA) (n = 10). Mean values of push-out bond strength for each group and root region (cervical, middle and apical) were calculated. Data were statistically analyzed with one-way ANOVA and Tukey's test (P < 0.05). Failure modes were evaluated using optical microscopy and scanning electron micrography (SEM).ResultsWithout being statistically significant, the bond strength of RelyX was higher (8.23 ± 4.46 MPa) when compared to that of Maxcem Elite (6.52 ± 3.68 MPa).ConclusionsSignificant differences (P < 0.05) were observed between the apical and cervical regions. More frequent (>60%) adhesive failures at the resin cement-dentine interface were observed.