Does the glaze application on Y-TZP surface improve the bond strength to pressed veneering ceramic?

Abstract

The objective of this study was to verify the influence of glaze application on the shear bond strength between Y-TZP and veneering ceramic. Thirty square-shaped blocks (12.5 × 15 × 1.5 mm) of sintered zirconia (Vita In Ceram YZ for inLab, VITA Zahnfabrik) were prepared, randomly divided into three groups (n = 10), according to the factor ‘glaze application’ (c – control/ g – powder and liquid/ gs – spray). On each zirconia surface, a cylinder of PM9 (Vita) ceramic was built (∅: 3 mm; height: 3 mm), according to the experimental group. Specimens were thermocycled (12,000 cycles/5 °C/55 °C ± 2 °C) and submitted to shear testing in a universal testing machine (1 mm/min). Analysis of fractured specimens ware performed through stereomicroscopy and SEM. Data were statistically analyzed through one-way ANOVA, Tukey’s test (5%) and Weibull's analysis. ANOVA revealed that the factor ‘glaze application’ (p = 0.001) was significant. The mean (±SD) shear bond data (MPa) were PM9c – 41.52 (±11.82); PM9g – 24.14 (±12.82); PM9gs – 21.06 (±14.48). There were no significant differences among glazed types for bond strength and Weibull modulus (p > 0.05), however the Characteristic strength (σ_o) decreased significantly after the application of the glaze, regardless of the group. The predominant type of failure was adhesive (76.66%) followed by mixed (23.34%). It can be concluded that, within the limitations of this study, the glazing application on Y-TZP surface, either powder and liquid or spray, did not improve the bond strength to pressed veneering ceramic.

Keywords:

• Zirconia
• ceramics
• glazing
• bond strength

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was funded in part by the Coordination for the Development of Higher Education Personnel – Brazil (CAPES) – Finance Code [001].