Push-out bond strengths: the Epiphany-Resilon endodontic obturation system compared with different pairings of Epiphany, Resilon, AH Plus and gutta-percha

AIM: To assess the bond strength of the new resin-based Epiphany-Resilon root canal filling system, and to compare this with bond strengths of different pairings of AH Plus, gutta-percha, Epiphany and Resilon. METHODOLOGY: A total of 65 extracted human single-rooted teeth were used. All teeth were instrumented using a set of ProTaper rotary instruments. Irrigation was performed with 15 mL of 1.25% NaOCl between each instrument and the smear layer was removed during and after instrumentation with 5 mL of 17% EDTA. The canal spaces were filled with different combinations of core and sealer using lateral condensation, as follows: group 1, AH Plus + gutta-percha; group 2, AH Plus + Resilon; group 3, Epiphany + Resilon; group 4, Epiphany + gutta-percha; group 5 (control), gutta-percha only. Cylinders of root dentine 1.13 (0.06)-mm long were prepared from the coronal sections of the 65 teeth. The test specimens were subjected to the push-out test method. After adhesion testing, the remaining sections were examined under a stereomicroscope at x 25 magnification to determine the nature of bond failure. The values of bond strength were analyzed by one-way analysis of variance (ANOVA) and the post hoc Tukey's test, with significance set at P < 0.05. RESULTS: The respective mean push-out test values for groups 1-5 were: 2.000 +/- 0.369, 1.380 +/- 0.154, 1.706 +/- 0.340, 2.857 +/- 0.523 and 0.078 +/- 0.027 MPa. Significant difference (P < 0.001) occurred between the groups. Multiple paired comparisons (Tukey's test) revealed that group 4 (Epiphany + gutta-percha) had significantly (P < 0.001) greater bonding strength than all the other groups; group 1 (AH Plus + gutta-percha) had significantly (P < 0.05) greater bonding strength than group 2 (AH Plus + Resilon); and group 5 (control) had significantly (P < 0.05) lower bonding strength than all the other groups. Inspection of the surfaces revealed the bond failure to be mainly adhesive to dentine for all groups. CONCLUSIONS: The Epiphany-Resilon combination (group 3) was not superior to that of the AH Plus-gutta percha combination (group 1).