Department of Dental Materials and Craniofacial Research Center, Dental School, Azad University (Tehran Branch), Tehran, Iran.
Dent Traumatol. 2013 Aug;29(4):323-7. doi: 10.1111/j.1600-9657.2012.01176.x. Epub 2012 Aug 13.
To analyze the push-out bond strength of Angelus WMTA (Angelus Dental Products), a nano-modification of WMTA (Kamal Asgar Research Center) and Bioaggregate (Innovative Bioceramix).
Sixty 2-mm-thick root sections were prepared from 60 single-rooted human teeth. The dentin disks were randomly divided into three groups (n = 20) and filled with Angelus WMTA, Nano-WMTA, or Bioaggregate, respectively. Push-out bond strength values of the specimens were measured by a universal testing machine and examined under scanning electron microscope at × 40 magnification to determine the nature of the bond failure. The data were analyzed with a Kruskal-Wallis test.
The greatest mean for push-out bond strength (138.48 ± 11.43 MPa) was observed for the nano-modification of WMTA. The values decreased to 110.73 ± 11.19 and 25.64 ± 5.27 MPa for Angelus WMTA and Bioaggregate, respectively. There were significant differences between the groups (P < 0.001). Inspection of the samples revealed the bond failure to be predominantly adhesive type except for the nano-modification group, as some samples also exhibited cohesive failures.
It is concluded that the force needed for the displacement of the nano-modification of WMTA (NWMTA) was significantly higher than for Angelus WMTA and Bioaggregate.
分析 Angelus WMTA（Angelus Dental Products）、纳米改性 WMTA（Kamal Asgar 研究中心）和 Bioaggregate（Innovative Bioceramix）的推出粘结强度。
从 60 颗单根人牙中制备 60 个 2 毫米厚的根段。牙本质圆盘随机分为三组（n = 20），分别用 Angelus WMTA、纳米 WMTA 和 Bioaggregate 填充。用万能试验机测量试件的推出粘结强度值，并在扫描电子显微镜下以 ×40 放大倍数检查，以确定粘结破坏的性质。用 Kruskal-Wallis 检验分析数据。
纳米改性 WMTA 的推出粘结强度平均值最大（138.48 ± 11.43 MPa）。Angelus WMTA 和 Bioaggregate 的值分别降低至 110.73 ± 11.19 和 25.64 ± 5.27 MPa。组间差异有统计学意义（P < 0.001）。对样品的检查表明，粘结破坏主要为黏附型，除纳米改性组外，一些样品还表现出内聚性破坏。
纳米改性 WMTA（NWMTA）的位移所需的力明显高于 Angelus WMTA 和 Bioaggregate。
