Influence of Adhesive Layer on Bonding Zirconia with Silane

Objectives: To evaluate the effects of an application of an adhesive layer on the bond strength of zirconia with different tranlsucency to resin cements.
Methods: 72 Zirconia slabs, 10 mm length, 5 mm width and 2 mm thick of zirconia NexxZr from Sagemax, Katana Ultratransluscent multilayer and Katana Multilayer for Noritake dental, each were made following manufacturer instructions for sintering processes. Samples were divided into 3 groups of 24 to receive coupling agents Monobond N (Ivoclar), Clearfil ceramic primer plus (Kuraray) and Z-prime ( BIsco). For each group after the silane application, half (n=12) received a thin coat of adhesive Tetric N Bond (Ivoclar) and the other half did not before being bonded to a prefabricated composite cylinder (2mm diameter) with Variolink Esthetic LC. Light cured for 20 second on both sides after removing excess. Specimens were tested in shear in an universal testing machine at 0.01 cm/min crosshead speed until failure. Data were stored In MPa and analyzed with a 3-way analysis of variance calculated at 0.05 significance level. Means were compared using Tukey HSD also calculated at 0.05 significance level.
Results: Means in MPa are shown on table.
Transluscency in zirconia does not have an impact on bond strength of resin cements if same protocols are followed.
There was no significant differences among zirconias nor coupling agents used. But the use of a thin coat of adhesive resin before cementing did have a negative significant effect of bond strength
Conclusions: Zirconia translucency does not affect bond strength
Different coupling agent produced same bond strength
The use of dental adhesive reduces bond strength to zirconia