Department of Prosthodontics, Faculty of Dentistry, Cukurova University, Adana, Turkey.
J Prosthodont. 2019 Jan;28(1):e310-e318. doi: 10.1111/jopr.12748. Epub 2018 Feb 11.
To compare the fracture mechanics, microstructure, and elemental composition of lithography-based ceramic manufacturing with pressing and CAD/CAM.
Disc-shaped specimens (16 mm diameter, 1.2 mm thick) were used for mechanical testing (n = 10/group). Biaxial flexural strength of three groups (In-Ceram alumina [ICA], lithography-based alumina, ZirkonZahn) were determined using the "piston on 3-ball" technique as suggested in test Standard ISO-6872. Vickers hardness test was performed. Fracture toughness was calculated using fractography. Results were statistically analyzed using Kruskal-Wallis test followed by Dunnett T3 (α = 0.05). Weibull analysis was conducted. Polished and fracture surface characterization was made using scanning electron microscope (SEM). Energy dispersive spectroscopy (EDS) was used for elemental analysis.
Biaxial flexural strength of ICA, LCM alumina (LCMA), and ZirkonZahn were 147 ± 43 MPa, 490 ± 44 MPa, and 709 ± 94 MPa, respectively, and were statistically different (P ≤ 0.05). The Vickers hardness number of ICA was 850 ± 41, whereas hardness values for LCMA and ZirkonZahn were 1581 ± 144 and 1249 ± 57, respectively, and were statistically different (P ≤ 0.05). A statistically significant difference was found between fracture toughness of ICA (2 ± 0.4 MPa⋅m ), LCMA (6.5 ± 1.5 MPa⋅m ), and ZirkonZahn (7.7 ± 1 MPa⋅m ) (P ≤ 0.05). Weibull modulus was highest for LCMA (m = 11.43) followed by ZirkonZahn (m = 8.16) and ICA (m = 5.21). Unlike LCMA and ZirkonZahn groups, a homogeneous microstructure was not observed for ICA. EDS results supported the SEM images.
Within the limitations of this in vitro study, it can be concluded that LCM seems to be a promising technique for final ceramic object manufacturing in dental applications. Both the manufacturing method and the material used should be improved.
比较基于光刻的陶瓷制造与压制和 CAD/CAM 的断裂力学、微观结构和元素组成。
使用圆盘状试件（直径 16mm，厚 1.2mm）进行力学测试（每组 n=10）。根据测试标准 ISO-6872 中的“活塞在 3 球上”技术，确定三组（In-Ceram 氧化铝[ICA]、基于光刻的氧化铝、ZirkonZahn）的双轴弯曲强度。进行维氏硬度测试。使用断裂形貌法计算断裂韧性。使用 Kruskal-Wallis 检验后进行 Dunnett T3（α=0.05）统计分析。进行威布尔分析。使用扫描电子显微镜（SEM）对抛光和断裂面进行特征描述。使用能量色散光谱（EDS）进行元素分析。
ICA、LCM 氧化铝（LCMA）和 ZirkonZahn 的双轴弯曲强度分别为 147±43MPa、490±44MPa 和 709±94MPa，差异具有统计学意义（P≤0.05）。ICA 的维氏硬度值为 850±41，而 LCMA 和 ZirkonZahn 的硬度值分别为 1581±144 和 1249±57，差异具有统计学意义（P≤0.05）。ICA（2±0.4MPa·m）、LCMA（6.5±1.5MPa·m）和 ZirkonZahn（7.7±1MPa·m）的断裂韧性差异具有统计学意义（P≤0.05）。LCMA 的威布尔模数最高（m=11.43），其次是 ZirkonZahn（m=8.16）和 ICA（m=5.21）。与 LCMA 和 ZirkonZahn 组不同，ICA 未观察到均匀的微观结构。EDS 结果支持 SEM 图像。
在本体外研究的限制内，可以得出结论，LCM 似乎是牙科应用中最终陶瓷制品制造的一种有前途的技术。制造方法和所用材料都应加以改进。
