在氧化基底支柱上保留晶冠:实验研究实验研究
Rawikorn Krongvanitchayakul1, Chatchai Kunavisarut1
1Department of Advanced General Dentistry, Faculty of Dentistry, Mahidol University, Bangkok, Thailand.
PloS one
|October 25, 2023
概括
支柱的热处理不会影响皇冠的保留. 表面的空气磨损显著提高了水泥结合强度和表面粗度,从而改善了冠状保持.
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
- 牙修复 牙修复 牙修复 牙修复 牙修复
背景情况:
- 使用热量将基支柱与基支柱分离,可以导致氧化.
- 这种热引起的氧化对皇冠保留的影响尚不清楚.
- 了解表面处理对于牙假肢中可靠的凝固至关重要.
研究的目的:
- 为了比较树脂结合强度和基支柱与基支柱之间的结合强度和故障模式,使用各种表面处理.
- 研究表面处理对支柱表面粗度和形态学的影响.
- 评估热氧化和空气磨损对冠与基支柱的结合强度的影响.
主要方法:
- 40个基支柱被分为四组:控制,氧化,空气磨损和氧化空气磨损.
- 在500°C的温度下进行热处理,以诱导特定群体的氧化.
- 表面分析包括分析和扫描电子显微镜 (SEM);热循环后测试了键强度.
主要成果:
- 与对照 (333.8nm) 和氧化 (321.0nm) 组相比,空气磨损显著增加了表面粗度 (Ra 476.0nm用于空气磨损,423.8nm用于氧化空气磨损).
- 与对照组 (237.6±46.3N) 和氧化组 (241.7±46.3N) 相比,空气磨损组 (372.9±113.2N) 的拉伸键强度显著更高.
- 失败类型在各组之间显示了统计学上显著的差异,表明债券完整性各不相同.
结论:
- 基支柱的热氧化不会对拉伸键强度,故障模式或表面粗性产生负面影响.
- 表面的空气磨损增强了表面粗性,并显著增加了皇冠凝固的保持强度.
- 这些发现表明,空气磨损是一种有益的表面处理方法,可以提高基冠和基支柱之间的结合强度.
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