Dental Materials ( IF 5 ) Pub Date : 2020-11-15 , DOI: 10.1016/j.dental.2020.10.015 Chao Liu , Atilim Eser , Thomas Albrecht , Vasiliki Stournari , Monika Felder , Siegward Heintze , Christoph Broeckmann
Objective
To determine the Weibull modulus , the characteristic strength ,the subcritical crack growth (SCG) parameters ( & ) as well as the lifetime durability of three dental ceramic materials in water: a polycrystalline yttria-stabilized zirconia (Zenostar MT O, YSZ, Ivoclar Vivadent/Wieland, Germany), a lithium disilicate glass ceramic (IPS e.max CAD, LD, Ivoclar Vivadent, Liechtenstein), and a zirconia-containing lithium silicate glass ceramic (Celtra Duo, ZLS, Dentsply Sirona Inc, USA).
Methods
30 specimens (Ø12 mm × 0.9 mm thickness) of each material were fabricated. The biaxial ring-on-ring bending tests at four stress rates (100, 10, 1, 0.1 MPa/s) were performed in water for all three ceramics. The results were used to determine the Weibull and SCG parameters, and to plot the Strength-Probability-Time (SPT) diagram.
Results
YSZ showed the highest (12.5) and highest (542 MPa), while the values for the glass ceramic materials were lower: for LD = 4.7, = 407 MPa, and for ZLS = 2.7, = 279 MPa. The for YSZ, LD and ZLS in water were 31.1, 13.7 and 16.6, respectively. The strength of YSZ decreased by 50% within a simulated period of 10 years, and for the glass ceramic materials the decrease was up to 80%.
Significance
Determining the Weibull and SCG parameters from the constant stress rate testing is an efficient methodology for ranking materials in terms of durability and longevity.
中文翻译:
牙科陶瓷材料的强度表征和寿命预测
目的
确定威布尔模量 ,特性强度 ,亚临界裂纹扩展(SCG)参数( 和 )以及三种牙科陶瓷材料在水中的使用寿命:多晶氧化钇稳定的氧化锆(Zenostar MT O,YSZ,伊沃克拉尔·瓦瓦登特/威兰德,德国),二硅酸锂玻璃陶瓷(IPS e.max CAD,LD, Ivoclar Vivadent,列支敦士登)和含氧化锆的硅酸锂玻璃陶瓷(Celtra Duo,ZLS,Dentsply Sirona Inc,美国)。
方法
每种材料制作了30个样品(Ø12mm×0.9 mm厚度)。双轴环在四个应力率下的弯曲测试对于所有三种陶瓷,均在水中进行了(100、10、1、0.1 MPa / s)测试。结果用于确定Weibull和SCG参数,并绘制强度-概率-时间(SPT)图。
结果
YSZ显示最高 (12.5)和最高 (542 MPa),而玻璃陶瓷材料的值较低:对于LD = 4.7, = 407 MPa,对于ZLS = 2.7, = 279兆帕。的水中的YSZ,LD和ZLS分别为31.1、13.7和16.6。在10年的模拟时间内,YSZ的强度降低了50%,而玻璃陶瓷材料的强度降低了80%。
意义
通过恒定应力率测试确定Weibull和SCG参数是一种根据耐久性和寿命对材料进行排名的有效方法。