Sahebi Safoora, Sadatshojaee Nooshin, Jafari Zahra
Department of Endodontics, Dental School, Shiraz University of Medical Sciences, Shiraz, Iran.
Iran Endod J. 2015;10(2):104-6. Epub 2015 Mar 18.
The aim of this experimental laboratory study was to evaluate the effect of different mixing and placement techniques on compressive strength (CS) of calcium-enriched mixture (CEM) cement.
CEM powder was mixed with its liquid either by hand mixing or amalgamator mixing. The mixture was loaded to cylindrical acrylic molds with 6.0±0.1 mm height and 4.0±1 mm diameter. Half of the specimens in each group were selected randomly and ultrasonic energy was applied to them for 30 sec. All samples were incubated for 7 days at 37(°)C. The CS test was performed by means of a universal testing machine. The data were analyzed by the two-way analysis of variance (ANOVA) and Tukey's post hoc tests. The level of significance was set at 0.05.
The maximum CS was seen in the amalgamator-mixed samples that did not receive ultrasonic agitation. The CS value of amalgamator-mixed samples was significantly higher than manually-mixed ones (P=0.003). Ultrasonic vibration did not change the CS of specimens.
According to the results, mixing with amalgamator increases the CS of CEM cement, while ultrasonic vibration had no positive effect.
本实验性实验室研究的目的是评估不同混合和放置技术对富钙混合物（CEM）水泥抗压强度（CS）的影响。
CEM粉末通过手工混合或研磨机混合与液体混合。将混合物装入高度为6.0±0.1毫米、直径为4.0±1毫米的圆柱形丙烯酸模具中。每组中一半的标本被随机选择，并对其施加30秒的超声能量。所有样品在37℃下孵育7天。通过万能试验机进行抗压强度测试。数据通过双向方差分析（ANOVA）和Tukey事后检验进行分析。显著性水平设定为0.05。
在未接受超声搅拌的研磨机混合样品中观察到最大抗压强度。研磨机混合样品的抗压强度值显著高于手工混合样品（P = 0.003）。超声振动未改变标本的抗压强度。
根据结果，使用研磨机混合可提高CEM水泥的抗压强度，而超声振动没有积极影响。
