Post-Graduate Program in Dentistry, School of Dentistry, Meridional Faculty, IMED, Passo Fundo, Rio Grande do Sul, Brazil.
PhD student, MSciD and PhD Post-Graduate Program in Oral Science (Prosthodontics Units), Faculty of Dentistry, Federal University of Santa Maria (UFSM), Santa Maria, Rio Grande do Sul, Brazil.
J Prosthet Dent. 2021 Jul;126(1):119-127. doi: 10.1016/j.prosdent.2020.03.032. Epub 2020 Jul 5.
Data comparing the fatigue performance of adhesively luted glass or polycrystalline ceramic systems for computer-aided design and computer-aided manufacturing (CAD-CAM) are scarce.
The purpose of this in vitro study was to evaluate and compare the fatigue performance of monolithic crowns manufactured from glass or polycrystalline CAD-CAM ceramic systems adhesively luted to a dentin analog.
Fifty-four pairs of standardized preparations of dentin analog (NEMA Grade G10) and simplified ceramic crowns of 1.5-mm thickness were obtained with 3 ceramic materials: lithium disilicate (LD) glass-ceramic (IPS e.max CAD); zirconia-reinforced lithium silicate (ZLS) glass-ceramic (Vita Suprinity); and translucent yttrium fully stabilized polycrystalline zirconia (Trans YZ) (Prettau Anterior). The simplified crowns (n=15) were adhesively cemented onto the preparations and subjected to step-stress fatigue test (initial load of 400 N, 20 Hz, 10 000 cycles, followed by 100-N increment steps until failure). Collected data (fatigue failure load [FFL] and cycles for failure [CFF]) were submitted to survival analysis with the Kaplan-Meier and Mantel-Cox post hoc tests (α=.05) and to Weibull analysis (Weibull modulus and its respective 95% confidence interval). Failed crowns were submitted to fractography analysis. The surface characteristics of the internal surface (roughness, fractal dimension) of additional crowns were accessed, and the occlusal cement thickness obtained in each luted system was measured.
Trans YZ crowns presented the highest values of FFL, CFF, and survival rates, followed by ZLS and LD (mean FFL: 1740 N>1187 N>987 N; mean CFF: 149 000>92 613>73 667). Weibull modulus and cement thickness were similar for all tested materials. LD presented the roughest internal surface, followed by ZLS (mean Ra: 226 nm>169 nm>93 nm). The LD and ZLS internal surfaces also showed higher fractal dimension, pointing to a more complex surface topography (mean fractal dimension: 2.242=2.238>2.147).
CAD-CAM monolithic crowns of Trans YZ show the best fatigue performance. In addition, ZLS crowns also showed better performance than LD crowns.
比较计算机辅助设计和计算机辅助制造（CAD-CAM）用玻璃或多晶陶瓷系统的粘固后疲劳性能的数据很少。
本体外研究的目的是评估和比较从玻璃或多晶 CAD-CAM 陶瓷系统制造的整体冠的疲劳性能，这些冠以粘固剂粘接到牙本质模拟物上。
使用 3 种陶瓷材料获得 54 对标准化牙本质模拟（NEMA Grade G10）和 1.5-mm 厚简化陶瓷冠的标准制备体：锂硅二硅酸盐（LD）玻璃陶瓷（IPS e.max CAD）；氧化锆增强锂硅玻璃陶瓷（ZLS）（Vita Suprinity）；半透明钇全稳定多晶氧化锆（Trans YZ）（Prettau Anterior）。将简化的冠（n=15）以粘固剂粘接到制备体上，并进行阶跃应力疲劳试验（初始负荷 400 N，20 Hz，10000 次循环，然后增加 100-N 增量步骤，直到失效）。收集的数据（疲劳失效负荷[FFL]和失效循环[CFF]）进行 Kaplan-Meier 和 Mantel-Cox 事后检验的生存分析（α=.05）和威布尔分析（威布尔模数及其相应的 95%置信区间）。对失效的牙冠进行断口分析。对额外牙冠的内表面（粗糙度、分形维数）的表面特性进行评估，并测量每个粘固系统中获得的牙合面粘固剂厚度。
Trans YZ 牙冠的 FFL、CFF 和存活率最高，其次是 ZLS 和 LD（平均 FFL：1740 N>1187 N>987 N；平均 CFF：149000>92613>73667）。所有测试材料的威布尔模数和水泥厚度相似。LD 呈现最粗糙的内表面，其次是 ZLS（平均 Ra：226 nm>169 nm>93 nm）。LD 和 ZLS 的内表面也显示出更高的分形维数，表明表面形貌更复杂（平均分形维数：2.242=2.238>2.147）。
CAD-CAM 整体牙冠的 Trans YZ 显示出最佳的疲劳性能。此外，ZLS 牙冠的性能也优于 LD 牙冠。
