Harini P, Mohamed Kasim, Padmanabhan T V
Final Year Undergraduate, Faculty of Dental Science, Sri Ramachandra University, Porur, Chennai, Tamil Nadu, India.
Indian J Dent Res. 2014 Jul-Aug;25(4):459-63. doi: 10.4103/0970-9290.142531.
To improve the flexural strength of polymethylmethacrylate (PMMA).
To evaluate whether the incorporation of titanium dioxide nanoparticles in polymethylmethacrylate (PMMA) increases the flexural strength and to compare the different concentrations of titanium dioxide nanoparticles and its relation to flexural strength.
Study was conducted in Sri Ramachandra University utilizing 40 specimens manufactured from clear heat polymerizing acrylic resin.
Forty specimens of clear heat polymerizing acrylic resin of dimensions 65 Χ 10 Χ 3 mm as per ISO 1,567 standardization were fabricated and were grouped into A (CONTROL) with no titanium dioxide (TiO2) nanoparticles, B with 0.5 gms of TiO 2 nanoparticles, C with 1 gm of TiO 2 nanoparticles and D with 2.5 gms of TiO 2 nanoparticles added.The concentrations of titanium dioxide in each group were 1 wt%, 2 wt% and 5 wt%. Universal testing machine INSTRON was used to load at the center of the specimen with a cross head speed of 1.50 mm/min and a span length of 40.00 mm.
ANOVA and multiple comparisons are carried out using the independent t-test.
The ANOVA result shows that there is a significant difference between the groups with respect to the mean flexural strength. Highest mean flexural strength is observed in Group D, while the lowest is seen in Group A. Independent t-test revealed that there was a statistical significance between Group A and Group D (0.041) and between Group B and Group D (0.028).
The results concluded that polymethylmethacrylate reinforced with different concentrations of titanium dioxide nanoparticles showed superior flexural strength than those of normal PMMA.
提高聚甲基丙烯酸甲酯(PMMA)的抗弯强度。
评估在聚甲基丙烯酸甲酯(PMMA)中加入二氧化钛纳米颗粒是否能提高抗弯强度,并比较不同浓度的二氧化钛纳米颗粒及其与抗弯强度的关系。
在斯里兰卡拉马钱德拉大学进行研究,使用由透明热聚合丙烯酸树脂制成的40个样本。
按照ISO 1567标准制作40个尺寸为65×10×3mm的透明热聚合丙烯酸树脂样本,并将其分为A组(对照组),不添加二氧化钛(TiO₂)纳米颗粒;B组添加0.5克TiO₂纳米颗粒;C组添加1克TiO₂纳米颗粒;D组添加⒉5克TiO₂纳米颗粒。每组中二氧化钛的浓度分别为1wt%、2wt%和5wt%。使用万能材料试验机INSTRON在样本中心加载,十字头速度为1.50mm/min,跨度为40.00mm。
使用方差分析(ANOVA)和独立t检验进行多重比较。
方差分析结果表明,各组之间在平均抗弯强度方面存在显著差异。D组的平均抗弯强度最高,而A组最低。独立t检验显示A组和D组之间(0.041)以及B组和D组之间(0.028)存在统计学意义。
结果表明,用不同浓度二氧化钛纳米颗粒增强的聚甲基丙烯酸甲酯的抗弯强度优于普通PMMA。