INTRODUCTION The aim of the present study was to investigate how different aging protocols can affect the flexural strength and phase transformations of yttrium-stabilized zirconia ceramics (Y-TZP) for monolithic restorations. MATERIALS AND METHODS Bar-shaped specimens from two zirconia ceramics bars were divided into three groups: a. no treatment (c), b. aging in an autoclave (a), and c. thermal cycling (t). The flexural strength was determined by the 3-point bending test and statistical analysis was performed to determine significant differences (p< 0.05). Weibull statistics was used to analyze the dispersion of strength values while surface microstructural analysis was performed through X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). RESULTS Aging did not significantly affect the flexural strength but differences were recorded between the two groups, with group A presenting higher strength values and m-phase percentages. CONCLUSIONS The observed differences between the two ceramics could be attributed to variations in composition and processing.

中文翻译：

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不同时效方案对两种单片氧化锆陶瓷抗弯强度和相变的影响

引言 本研究的目的是研究不同的老化方案如何影响整体修复的钇稳定氧化锆陶瓷 (Y-TZP) 的抗弯强度和相变。材料与方法 来自两根氧化锆陶瓷棒的棒状试样分为三组： a．不处理 (c), b. 在高压釜中老化 (a)，和 c. 热循环 (t)。抗弯强度通过三点弯曲试验确定，并进行统计分析以确定显着差异（p < 0.05）。威布尔统计用于分析强度值的分散，而表面微观结构分析则通过 X 射线衍射分析 (XRD)、傅里叶变换红外光谱 (FTIR) 和扫描电子显微镜 (SEM) 进行。结果老化对弯曲强度没有显着影响，但两组之间存在差异，A组具有更高的强度值和m相百分比。结论 两种陶瓷之间观察到的差异可归因于成分和加工的变化。