在人造老化后,阴影对石的相变化和屈曲强度的影响
Sebastian Wille1, Rüdiger Möller1, Matthias Kern1
1Department of Prosthodontics, Propaedeutics and Dental Materials, School of Dentistry, Christian-Albrechts University at Kiel, Germany.
概括
彩色石对热水老化具有较强的抗性,染色可能会阻碍相变. 然而,一种有色 (A3) 显示在模拟后,屈曲强度显著下降.
科学领域:
- 材料科学 材料科学 材料科学
- 生物材料工程 生物材料工程
- 牙科陶 牙科陶 的使用.
背景情况:
- 是由于其高强度和生物相容性而广泛使用的牙科陶.
- 的相变化会影响其机械性能和长期稳定性.
- 中配色剂可能会影响其对老化过程的反应.
研究的目的:
- 为了研究不同颜色的高强度 (3Y-TZP) 在老化后的相位转换和屈曲强度.
- 为了比较水热老化 (自) 和机械应力 (模拟) 对的影响.
- 评估颜色对的抗退化能力的影响.
主要方法:
- 三组 (无色,A3,D3) 经历了自闭室老化 (134°C,70小时) 和模拟 (120万个周期).
- 使用X射线衍射 (XRD) 监测相变.
- 使用4点曲试验测量了曲强度,该试验是在老化协议之前和之后进行的.
主要成果:
- 与无色基相比,有色基在水热老化过程中对相变的抗性增加.
- 自体老化在30小时内诱导了未染色的显著单临床相形成,而染色需要70小时.
- 在模拟后没有观察到任何显著的相变,但A3彩色体显示出屈曲强度的统计显著下降.
结论:
- 染色溶液中的金属氧化物可能会阻碍石的热水相转化.
- 虽然有色石对热水老化有更强的抗性,但机械应力仍然会影响其屈曲强度.
- 需要进一步的研究,以了解在机械负荷后,彩色石的屈曲强度降低背后的机制.
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