Evaluation of hardness and fracture toughness, coupled with microstructural analysis, of zirconia ceramics stored in environments with different pH values.

摘要: The aim of this study was to evaluate the effects pH changes in oral cavity on mechanical properties zirconia and feldspathic ceramics. Bilayered zirconia-feldspathic samples were prepared from three different commercial brands Y-TZP blocks: Zirkonzahn, Cercon, Everest. Samples stored artificial saliva with values (3.5, 7.0, 10.0) for 10 days at 37°C. Flexural strength, Vickers hardness, fracture toughness calculated after subjected biaxial flexure test. Microstructural analysis materials also performed.Data analyzed by one-way variance (ANOVA), multiple comparisons performed using Tukey's test (α=0.05). Acidic alkaline environments adversely affected zirconia, resulting material degradation, loss stabilizer content, increase tetragonal-monoclinic phase transformation. Commercial dental blocks have varied properties, but they are generally susceptible degradation when exposed corrosive environments.