Department of Endodontics, Faculty of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
Int Endod J. 2010 Apr;43(4):312-20. doi: 10.1111/j.1365-2591.2010.01683.x.
To evaluate the influence of various mixing procedures including ultrasonic vibration, trituration of customized encapsulated mineral trioxide aggregate (MTA) and condensation on the Vickers surface microhardness of MTA.
ProRoot MTA Original, ProRoot MTA (white), MTA-Angelus (grey) and MTA White Angelus (white) were prepared using several mixing techniques including ultrasonic vibration, trituration of customized encapsulated MTA and conventional condensation. Twelve experimental groups (four materials: three techniques) were evaluated, each with 35 samples. All samples were incubated after preparation and subjected to Vickers surface microhardness testing after 4 and 28 days. Data was were subjected to a two-way anova.
At 28 days, the surface microhardness value was significantly greater for all experimental groups compared to 4 days after mixing (P < 0.00001). The application of ultrasonic energy to MTA produced significantly higher surface microhardness values compared to the other mixing techniques at both 4 and 28 days (P < 0.0001). However, no significant difference existed between condensation and trituration techniques at both time intervals. Regardless of the mixing technique employed, a significant difference (P < 0.0001) was observed in surface microhardness value between all types of MTA apart from between Angelus grey and ProRoot white at both 4 and 28 days, both of which produced the highest values.
Compared to trituration and condensation techniques, the application of ultrasonic energy to MTA produced a significantly higher surface microhardness value at both 4 and 28 days. Irrespective of mixing technique, ProRoot white and Angelus grey had the highest surface microhardness values. Trituration of encapsulated, premeasured MTA and water provides a standardiszed method of mixing that produces MTA slurries with more controllable handling characteristics.
评估包括超声振动、定制封装矿化三氧化物聚合体（MTA）的研磨和压缩在内的各种混合程序对 MTA 的维氏表面显微硬度的影响。
使用包括超声振动、定制封装 MTA 的研磨和常规压缩在内的几种混合技术来制备 ProRoot MTA Original、ProRoot MTA（白色）、MTA-Angelus（灰色）和 MTA White Angelus（白色）。评估了 12 个实验组（四种材料：三种技术），每个组有 35 个样本。所有样本在制备后进行孵育，并在 4 天和 28 天后进行维氏表面显微硬度测试。数据采用双因素方差分析。
在 28 天，与混合后 4 天相比，所有实验组的表面显微硬度值均显著增加（P < 0.00001）。在 4 天和 28 天，与其他混合技术相比，应用超声能量于 MTA 可产生显著更高的表面显微硬度值（P < 0.0001）。然而，在两个时间间隔，压缩和研磨技术之间没有显著差异。无论采用哪种混合技术，在 4 天和 28 天，所有类型的 MTA 之间的表面显微硬度值都存在显著差异（P < 0.0001），除了 Angelus 灰色和 ProRoot 白色之间，这两者产生了最高的值。
与研磨和压缩技术相比，在 4 天和 28 天，应用超声能量于 MTA 可产生显著更高的表面显微硬度值。无论混合技术如何，ProRoot 白色和 Angelus 灰色具有最高的表面显微硬度值。研磨定制、预测量的 MTA 和水提供了一种标准化的混合方法，可产生具有更可控处理特性的 MTA 糊剂。
