Shear Bond Strength of Silanes Reinforced Porcelains After Surface Treatment

Objectives: Objectives: to evaluate shear bond strength of different silanes to lithium disilicate and zirconia, after two different surface treatment.
Methods: Methods: 80 samples, 5x10 mm of each Emax Press and ZirCAD zirconia based (Ivoclar Vivadent) were sintered following manufacturer’s instructions before being embedded in acrylic and polished. Each group was divided into 2 sub-groups of 40 specimens, half was etched with hydrofluoric acid 9.0% for 20s and the other half (n=40) was sandblasted with 50 microns particle size aluminum oxide, each sub-group was then divided into four groups (n=10) to receive one of four silanes: Bis Silane (BISCO), Silane (Ultradent Prods.), Monobond (Ivoclar/Vivadent), and Clearfil Ceramic Primer (Kuraray), all following manufacturer’s instructions.
2 mm diameter prefabricated composite cylinders (Brilliant, Coltene) were roughened and cemented on each sample with Variolink II (Ivoclar Vivadent) after a previous coat of Tetric N-Bond (Ivoclar Vivadent), applying a 500 gr force and eliminating excess before light curing. Specimens were stored for 7 days at 37° C in 100% relative humidity before tested in shear at 0.1 cm/min speed until failure. Data were stored in MPa and analyzed with a three-way ANOVA and means were compared with Tuke HSD test, both calculated at a 0.05 significance level.
Results: Results: Means and standard deviation in MPa are shown on table. There was a statistical difference among silanes. For lithium disilicate, etching produces a higher SBS than sandblasting, as recommended by manufacturer. Sandblasting produces a higher SBS in Zirconia for all silanes except Silane from Ultradent Prods.
Conclusions: Conclusions: Sandblasting is a better surface treatment for Zirconia, and acid etching is better for lithium disilicate