Abstract The aim of this work was to study the degradation of yttria-stabilized tetragonal zirconia (Y-TZP) directly exposed to the oral environment. Four groups of Y-TZP were tested G1: TZ-PX-242A, Zpex®; G2: TZ-PX-357, Zpex Yellow®; G3: ProtMat®, and G4: LAVA Frame®. The samples were attached to the base of temporary full dentures of patients and aged for 100 days. In this way, one surface of the samples was exposed to the oral environment. The samples (25 × 2 × 1.5 mm) were cut from noncommercial (G1 and G2) and commercially available (G3 and G4) presintered zirconia blocks. Quantitative and qualitative analyses were performed by X-ray fluorescence (XRF). Microstructural characterization was performed by scanning electron microscopy (SEM), X-ray diffraction (XRD), 3D surface roughness measurements and grain size measurements. The mechanical properties were determined by a four-point bending test. The data were analyzed by one-way ANOVA (p ≤ 0.05), Tukey's test and Weibull analysis. The results showed a tetragonal-monolithic transformation in the zirconia after oral aging. The surface roughness increased in all groups, and groups G3 and G4 showed increases in their flexural strengths.

中文翻译：

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Y-TZP陶瓷的口腔降解

摘要 这项工作的目的是研究直接暴露在口腔环境中的氧化钇稳定的四方氧化锆 (Y-TZP) 的降解。测试了四组 Y-TZP G1：TZ-PX-242A、Zpex®；G2：TZ-PX-357，Zpex Yellow®；G3：ProtMat®，和 G4：LAVA Frame®。将样品贴在患者临时全口义齿的基托上，老化100天。以此方式，样品的一个表面暴露于口腔环境。样品 (25 × 2 × 1.5 mm) 是从非商业（G1 和 G2）和市售（G3 和 G4）预烧结氧化锆块上切割下来的。通过 X 射线荧光 (XRF) 进行定量和定性分析。通过扫描电子显微镜 (SEM)、X 射线衍射 (XRD)、3D 表面粗糙度测量和晶粒尺寸测量进行微观结构表征。机械性能通过四点弯曲试验确定。数据通过单向方差分析 (p ≤ 0.05)、Tukey 检验和 Weibull 分析进行分析。结果表明，氧化锆在口腔老化后会发生四方-整体转变。所有组的表面粗糙度都增加，G3 和 G4 组的抗弯强度增加。