收缩应力是由收缩过程中的弹性模量决定的,而不是最终的弹性模量
Daranee Tantbirojn1, Jared Quave2, Anne E Hill1
1Department of General Dentistry, College of Dentistry, University of Tennessee Health Science Center, Memphis, TN, USA.
概括
牙复合材料中的聚合收缩与恢复寿命有关. 一个高的早期弹性模量,而不是最终的度,显著影响侧曲和牙的残留应力.
科学领域:
- 牙科材料科学 牙科材料科学
- 生物材料工程 生物材料工程
- 恢复性牙科 恢复性牙科
背景情况:
- 基于树脂的复合材料的聚合收缩是影响牙科修复寿命的关键因素.
- 了解收缩,弹性模量和残余应力之间的相互作用对于改善临床结果至关重要.
研究的目的:
- 为了研究聚合缩小和弹性模量发展在散装可流动复合材料之间的关系.
- 为了确定这些特性如何影响骨曲和由此产生的恢复牙内的残余应力.
主要方法:
- 三种批量填充可流动复合材料在用MOD制剂的类型牙前中进行了测试.
- 脊椎曲通过扫描测量,使用张力计测量后凝收缩,通过四点曲测量弹性模量.
- 使用ANOVA (α=0.05) 分析数据.
主要成果:
- 在复合材料中,骨曲率差异很大 (p=0.001),纤维增强复合材料的曲率 (17μm) 比传统的可流材料 (7μm) 高.
- 尽管收缩率较低 (0.53%),但纤维增强复合材料的早期弹性模量比其他复合材料 (2GPa) 高 (15分钟时8GPa).
- 弹性模块显著增加了24小时 (12GPa).
结论:
- 高弹性模块的快速发展否定了低聚合缩小的好处.
- 早期的弹性模量,特别是在收缩阶段,是侧曲和残余应力的主要决定因素.
- 恢复寿命受弹性模量发展的速度的影响,而不仅仅是最终的材料刚度.
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