Various Primers Effect on Resin-cement Adhesion to Zirconia and Lithium-disilicate

Objectives: The objective of the following study is to evaluate (in vitro) the shear bond strength (SBS) of adhesive resin cement to Zirconia and lithium-disilicate ceramics while using various ceramic primers.
Methods: SBS test was performed in accordance with ISO 29022. Sandblasted (n=8) and un-sandblasted (n=8) Zirconia blocks (ZirCom Zirkonblank, Compro-dent ) and Lithium di-silicate blocks (E.max Cad LTA2, Ivoclar-Vivaden) were used for each test group. All experimental groups were surface treated with three different ceramic primers: Q-Ceram,BJM (QC), Z-Prime Plus, Bisco (ZP), and Clearfil Ceramic-Primer, Kuraray (CR). High-Q-Bond Adhesive Resin-Cement, BJM was applied on all substrates. Specimens were stored for 24 hours at 37°C in 100% humidity. Specimens debonded in shear utilizing the Ultradent shear jig on a Shimadzu AGS-X universal testing machine at a crosshead speed of 1.0 mm/min. Mean SBS (MPa) was analyzed with one-way analysis of variance ANOVA (p<0.05).
Results: For Zirconia, group QC yielded the highest values of SBS both for un-sandblasted (23.7±3.5 MPa) and for sandblasted (20.1±5.0 MPa) blocks, while ZP group yielded (16.1±5.0 MPa) and (16.2±1.5), and CR group (17.9±2.7) and (20.9±3.0) respectively. For Lithium Di-silicate group QC exhibited higher results as well, (17.2±2.0 MPa) for un-sandblasted and (14.1±2.9) for sandblasted blocks. ZP group yielded (7.6±2.2 MPa) and (6.6±2.0), and CR group (5.7±2.4) and (12.6±4.9) respectively.
Conclusions: Q-Ceram Primer demonstrated better values in all examined groups. In addition, it can be concluded that sandblasting does not enhance SBS, particularly for QC and ZP groups.