全面复合树脂填充剂颗粒的特征说明
Jorge Perdigão1, Fernanda P Zatt2, Guilherme C Lopes2
1Department of Restorative Sciences, University of Minnesota School of Dentistry, Minneapolis, Minnesota, USA.
概括
扫描电子显微镜和热重力测量分析揭示了通用复合树脂中的各种填充颗粒形态和质量分数. 测量到的填充剂含量往往与制造商的说法不一致,突出显示了材料的变化.
科学领域:
- 牙科材料科学 牙科材料科学
- 在牙科的纳米技术.
- 聚合物化学 聚合物化学
背景情况:
- 通用复合树脂 (CRs) 在修复牙科中被广泛使用.
- 了解它们的填料成分对于预测性能至关重要.
- 现有的文献提供了制造商报告的填充剂 wt%,这可能不反映实际内容.
研究的目的:
- 使用扫描电子显微镜 (SEM) 在普遍CR中描述填充物颗粒形态和分布.
- 使用热重力测量分析 (TGA) 确定剩余填料质量分数 (填料重量%) .
- 为了比较测量的填料 wt% 与文献中报道的值.
主要方法:
- 分析了7个通用CR和2个对照CR.
- 在在乙中溶解CRs后分离了填充物颗粒.
- 使用SEM检查粒子大小和分布 (×5000×80,000).
- 通过将CR加热到1000°C进行TGA,以确定剩余填充剂质量.
主要成果:
- SEM揭示了不同的填料分布:单模 (OM),双模 (EO,EU,FU,ST,VO,EM) 和三模 (CO,SS).
- 粒子形状各不相同,不规则的大颗粒 (>2μm) 在CO,EU,ST,VO中,纳米粒子集群在EM,FU,SS中.
- 测量到的填料重量%在66.27% (EU) 到78.28% (VO) 之间,与大多数材料的文献值有很大的差异,特别是欧盟 (-18.2%).
结论:
- 填充剂颗粒大小和分布在通用复合树脂之间有很大差异.
- 来自同一制造商的材料 (EO/OM,EM/FU) 显示出类似的填充材料特性.
- 测量到的填料 wt%经常与报告的文献值相矛盾,表明材料表征或报告中的潜在不准确性.
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