Aflatoonian Khotan, Hamze Faeze, Mohammadibassir Mahshid
Specialist in Restorative Dentistry, Private practice, Pasdaran street, Tehran, Iran.
Department of Operative Dentistry, School of Dentistry, Shahed University, Tehran, Iran.
BMC Oral Health. 2025 Apr 11;25(1):534. doi: 10.1186/s12903-025-05810-z.
To compare the effect of deglazing and aging on biaxial flexural strength (FS) of high translucent (HT) zirconia.
40 disc-shaped specimens (12 × 1.2 mm) of HT zirconia (3Y-PSZ, Upcera HT) were sintered after milling, glazed(G) and randomly assigned equally into 4 experimental groups: G) glazing; G-A) glazing, aging; DG-A) deglazing, aging; and NG-A) non-glazing, aging. A sequence of three methods was used for aging; hydrothermal, pH-cycling, and load cycling. FS(flexural strength) of all specimens was measured and one specimen from each group underwent X-ray diffraction (XRD) for assessment of phase transformation (t-m). Distribution of data was evaluated using the Kolmogorov -Smirnov test, and with respect to the confidence interval of 95%, data were analyzed using 1-way ANOVA with statistical software (IBM SPSS Statisticsv20.0) to compare the mean flexural strength values among the 4 groups. When significant differences were found, the mean values were compared using Tukey's honest significant difference (HSD) test (α = 0.05).
FS of glazed specimens (1092.78 ± 175.40 MPa) did not decrease after aging (1141.11 ± 117.43 MPa, P = 0.872). FS of DG-A (1338.22 ± 175.13 MPa) and NG-A (1320.44 ± 77.44 MPa) groups was significantly higher than that of G and GA groups (P < 0.005). XRD revealed monoclinic phase in DG-A (4.23%) and NG-A (7.63%) groups.
Loss of glaze layer and no glazing had no significant effect on FS of high translucent Y-PSZ after aging.
比较除釉和老化对高透氧化锆双轴弯曲强度（FS）的影响。
40个高透氧化锆（3Y-PSZ，Upcera HT）盘状试样（12×1.2毫米）在研磨后烧结、上釉（G），并随机等分为4个实验组：G）上釉；G-A）上釉、老化；DG-A）除釉、老化；NG-A）未上釉、老化。采用水热、pH循环和加载循环三种方法进行老化处理。测量所有试样的FS（弯曲强度），每组取一个试样进行X射线衍射（XRD）以评估相变（t-m）。使用Kolmogorov-Smirnov检验评估数据分布，并在95%置信区间下，使用统计软件（IBM SPSS Statistics v20.0）通过单因素方差分析来比较4组的平均弯曲强度值。当发现显著差异时，使用Tukey's真实显著性差异（HSD）检验（α = 0.05）比较平均值。
上釉试样的FS（1092.78±175.40兆帕）在老化后未降低（1141.11±117.43兆帕，P = 0.872）。DG-A组（1338.22±175.13兆帕）和NG-A组（1320.44±77.44兆帕）的FS显著高于G组和GA组（P < 0.005）。XRD显示DG-A组（4.23%）和NG-A组（7.63%）中存在单斜相。
老化后，釉层的缺失和未上釉对高透Y-PSZ的FS没有显著影响。
