Journal of Adhesion Science and Technology, Vol.32, No.10, 1055-1065, 2018
Influence of silicoating, etching and heated glaze treatment on the surface of Y-TZP and its impact on bonding with veneering ceramic
The study aimed to investigate the influence of surface treatments of Y-TZP on its topography and their impact on shear bond strength (SBS) of Y-TZP to veneering porcelain. Thirty-four zirconia cubes (Cercon) (10 x 10 x 10 mm(3)) were divided randomly into 3 groups (n = 11) according to the different surface treatments, Silica Coating (SC); Hot Solution Etching (HE); and Heat Treatment after porcelain glaze and powder application (GP). Porcelain application (IPs e.max) was performed after surface treatment using a standardized technique. Porcelain application (Ceramco-3) was also performed on 10 metal cubes (I BOND 2) as controls (MC). Specimens were subjected to thermocycling (5-55 degrees C, 20,000 cycles) followed by SBS testing in a universal testing machine. Surface topography was assessed by scanning electron microscopy and surface roughness (Image J). SC developed significantly higher SBS (42.10 +/- 5.84 MPa) of Y-TZP to veneering ceramics compared to treatment by HE (24.0 +/- 6.4 MPa), GP (23.30 +/- 4.72), and the MC (29.3 +/- 5.4 MPa) control (p < 0.05). SBS among HE, GP and MC specimens was comparable (p > 0.05). Y-TZP specimens treated with SC and HE showed high surface roughness compared to GP. Silicoating of Y-TZP prior to veneering can potentially reduce the high failure rates of zirconia-based restorations by enhancing the chemical bond between the core and the veneer materials.