Department of Oral and Maxillo-Facial Sciences, Sapienza University of Rome, Rome, Italy.
Eur Rev Med Pharmacol Sci. 2020 May;24(10):5201-5208. doi: 10.26355/eurrev_202005_21301.
The aim of this study was to compare both the elastic modulus (EM) and the flexural strength (FS) of two materials used in dental prosthesis, namely polymethylmethacrylate (PMMA) and polymethylmethacrylate reinforced with graphene (G-PMMA).
Twenty rectangular samples were manufactured by a milling machine and divided into two groups (n= 10/group): Group 1, PMMA; Group 2, G-PMMA. The specimens were subjected to a three-point bending test conducted in the elastic range to evaluate EM. A similar test was protracted until fracture to evaluate FS. Data on EM and FS were statistically analyzed with independent-samples t-test in order to compare the two groups. A scanning electron microscope (SEM) (5.00 kx and 1.00 kx magnification) was used to evaluate the morphology of sample's fracture.
Compared to PMMA samples, each G-PMMA sample showed significantly higher values of FS (p <0.001) and EM (p <0.001). SEM images analysis showed an inhomogeneous fracture morphology in G-PMMA samples.
The results show that G-PMMA is a promising material to be used for prosthetic purposes. This is demonstrated by a significant increase in both peak load and bending stiffness, resulting from the bending test performed on G-PMMA samples. Furthermore, the latter exhibit greater homogeneity in their mechanical behavior, supporting the potential value of this material in dental prosthesis.
本研究旨在比较两种用于义齿修复的材料的弹性模量（EM）和弯曲强度（FS），即聚甲基丙烯酸甲酯（PMMA）和石墨烯增强聚甲基丙烯酸甲酯（G-PMMA）。
通过铣床制造 20 个矩形样本，并将其分为两组（每组 n=10）：第 1 组，PMMA；第 2 组，G-PMMA。对试样进行三点弯曲试验，在弹性范围内进行，以评估 EM。进行类似的试验直至断裂，以评估 FS。使用独立样本 t 检验对 EM 和 FS 数据进行统计分析，以比较两组。使用扫描电子显微镜（SEM）（5.00 kx 和 1.00 kx 放大倍数）评估样品断裂的形态。
与 PMMA 样本相比，每个 G-PMMA 样本的 FS（p<0.001）和 EM（p<0.001）值均显著更高。SEM 图像分析显示 G-PMMA 样本的断裂形态不均匀。
结果表明，G-PMMA 是一种有前途的用于义齿修复的材料。这是通过在 G-PMMA 样本上进行的弯曲试验导致峰值载荷和弯曲刚度的显著增加来证明的。此外，后者在机械行为上表现出更大的均匀性，支持该材料在牙科修复中的潜在价值。
