BIAXIAL FLEXURAL STRENGTH OF ZIRCONIA-BASED CERAMIC CORE WITH VARIOUS VENEER MANUFACTURERS

Abstract

The aim of this study is to evaluate the biaxial flexural strength (BFS) of zirconia-based ceramic when used with veneering porcelains from the same and different manufacturers. Zirconia core material (Katana) and five veneering porcelains (Cerabien ZR, Lava Ceram, Cercon Ceram Kiss, IPS e.max Ceram and VITA VM9) were selected. The bilayered disc specimens (diameter: 12.50 mm, thickness: 1.50 mm) were prepared following ISO standard 6872:2008 by the same person for each pairing into five groups of veneering porcelains (n = 12), using the powder/liquid layering technique (core 0.75 mm, veneer 0.75 mm). After 20,000 cycles of thermocycling, BFS tests were conducted using a universal testing machine (Instron). The data were analyzed with one-way ANOVA and Tukey Post Hoc multiple comparison tests (α = 0.05). The mean ± SD of BFS were as followed: Cerabien ZR = 489.56 ± 67.00 MPa, Lava Ceram = 602.55 ± 76.31 MPa, Cercon Ceram Kiss = 705.94 ± 65.89 MPa, IPS e.max Ceram = 496.94 ± 64.78 MPa and VITA VM9 = 483.72 ± 67.37 MPa. The statistical analysis showed that Cercon Ceram Kiss significantly had the highest BFS, followed by Lava Ceram. The BFS of Cerabien ZR, IPS e.max Ceram and VITA VM9 were not significantly different but were significantly lower than the other two groups above. Concluded from the result, to obtain for the strength, zirconia core might not be used to pair with veneering porcelain from the same manufacturer as recommended. The optimal compatibility of zirconia and veneering porcelain might result from many other physical factors of the material and needs further investigation.