This study evaluated the fatigue failure load, number of cycles for failure and survival probability of 2nd and 3rd generation yttrium-stabilized zirconia (YSZ) adhesively cemented to a dentin analogue substrate. Disc-shaped specimens (n = 10; Ø = 10 mm; thickness = 1.0 mm) were produced from four 2nd generation YSZs (Lava Plus, 3M ESPE; Vita In-Ceram YZ-HT, VITA Zahnfabrik; Zirlux FC, Ivoclar Vivadent; Katana ML-HT, Kuraray) and two 3rd generation YSZs (Katana UTML and Katana STML, Kuraray). Each YSZ disc was adhesively cemented (Multilink Automix System) onto its dentin analogue pair (epoxy resin, Ø = 10 mm; thickness = 2.5 mm). Fatigue tests were conducted through step-stress approach (load ranging from 400 to 2600 N; step-size of 200 N; 20,000 cycles per step, 20 Hz) and the obtained data were analyzed using Kaplan Meier and Mantel-Cox tests. Surface topography and phase transformation (m-, t-, and c-phases) inspections after particle air-abrasion of the YSZs were performed, as well as fractographic analysis of the failed specimens. Second-generation zirconia materials presented higher fatigue failure load, number of cycles for failure, and survival probability than 3rd generation. Similar topographical characteristics of the YSZs could be noted. Phase transformation (t- to m-phase) after YSZ air-abrasion was only observed for 2nd generation materials. All failures started from the surface/sub-surface defects located at the cementation interface. 2nd generation zirconia presented higher load-bearing capacity under cyclic loading than 3rd generation materials.

这项研究评估了粘结在牙本质类似物基质上的第二代和第三代钇稳定氧化锆（YSZ）的疲劳破坏载荷，破坏循环数和存活概率。由四个第二代YSZ（Lava Plus，3M ESPE； Vita In-Ceram YZ-HT，VITA Zahnfabrik； Zirlux FC，Ivoclar Vivadent； Nova）生产了圆盘形标本（n = 10；Ø= 10 mm；厚度= 1.0 mm）。 Katana ML-HT，可乐丽）和两个第三代YSZ（Katana UTML和Katana STML，可乐丽）。将每个YSZ圆盘粘接到其牙本质类似物对（环氧树脂，Ø= 10 mm；厚度= 2.5 mm）上（Multilink Automix System）。通过阶跃应力方法（载荷范围为400至2600 N；阶跃大小为200 N；每步20,000个循环，20 Hz）进行疲劳测试，并使用Kaplan Meier和Mantel-Cox测试分析获得的数据。在对YSZ进行空气粒子磨损后，进行了m，t和c相检查，并对断裂的样品进行了分形分析。与第三代相比，第二代氧化锆材料具有更高的疲劳破坏载荷，破坏循环次数和存活概率。可以注意到YSZ的类似地形特征。仅在第二代材料中观察到YSZ空气磨损后的相变（t相到m相）。所有故障都是从位于胶结界面的表面/亚表面缺陷开始的。第二代氧化锆在循环载荷下比第三代材料具有更高的承载能力。