Biaxial Flexural Strength of Zirconia-Based Ceramic Core with Veneering Porcelain from Various Manufacturers

Abstract

Abstract Objective: To evaluate the biaxial flexural strength (BFS) of zirconia-based ceramic veneering with porcelain from the same and different manufacturers.Materials and Methods: Zirconia core material (Katana) and 4 veneering porcelains (Cerabien ZR, Lava Ceram, Cercon Ceram Kiss and IPS e.max Ceram) were selected. The bilayered disc specimens (diameter: 12.50 mm, thickness: 1.50 mm; core 0.75 mm, veneer 0.75 mm) were prepared into 4 groups according to veneering porcelain (n = 12), using the powder/liquid layering technique. After 20,000 times of thermocycling, BFS following ISO standard 6872:2008 were tested using universal testing machine (Instron). The data were analyzed with one-way ANOVA and Tukey Post Hoc multiple comparison tests (α = 0.05). Results: The mean ± SD of BFS were as followed, Cerabien ZR = 489.56 ± 67.00, Lava Ceram = 602.55 ± 76.31, Cercon Ceram Kiss = 705.94 ± 65.89 and IPS e.max Ceram = 496.94 ± 64.78 MPa. The statistical analysis showed that Cercon Ceram Kiss had significantly highest BFS, followed by Lava Ceram. The BFS of Cerabien ZR and IPS e.max Ceram were not significantly different but were significantly lower than the other two veneering porcelains. Conclusion: To obtain the good strength, zirconia core might not be used to pair with veneering porcelain from the same manufacturer as recommended. Key words: Biaxial flexural strength (BFS), Bilayered disc specimen,  Thermocycling, Veneering porcelain, Zirconia core.