Influence of 10-MDP Adhesive System on Shear Bond Strength of Zirconia-Composite Interfaces

Introduction: This in-vitro study investigated the initial 24h bond strength between different composites and zirconia after application of four different adhesive systems. Methods: A total of 120 specimens of zirconia (InCoris, Sirona, Germany, Bernsheim) were ground with a 165 µm grit rotating diamond disc. Thirty specimens were each additionally treated with Cimara Zircon “CZ” (VOCO GmbH, Germany, Cuxhaven), Futurabond U “FBU” (VOCO GmbH), Futurabond M+ “FBM” (VOCO GmbH) or Futurabond M+ in combination with the DCA activator “FBMD” (VOCO GmbH). One of three different types of composites – BifixSE (“BS”), BifixQM (“BQ”) or GrandioSO (“G”) (VOCO GmbH) – was bonded to ten specimens each in every group. Shear bond strength (SBS) was determined in a universal testing machine. Statistical analysis was performed with ANOVA and the Tukey test. Results: FBM and FBMD gave higher SBS than CZ and FBU in combination with all tested composites. In comparison to FBU, FBM gave statistically significant increases in SBS with BifixSE (19.4±5.7 MPa) (P < 0.013) and with GrandioSO (19.1±4.4 MPa) (P < 0.021). None of the other comparisons was statistically significant. Conclusion: The new 10-MDP-containing adhesive systems FBM and FBMD increases initial SBS between composites and zirconia in comparison to CZ and FBU.