混凝土类型对带有或不带有宫边缘移动的圆王冠边缘微裂纹的影响:一个体外研究
1*Ra'fat I. Farah, BDS, MSc, associate professor, Department of Prosthetic Dental Sciences, College of Dentistry, Qassim University, KSA, Al-Mulaydah, Qassim, KSA.
Operative dentistry
|February 5, 2025
概括
生物活性水泥和粘合树脂在减少基冠的微泄漏方面表现出卓越的性能. 较高的边缘显示泄漏率低于深的边缘,无论水泥类型如何.
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:
- 微漏是影响间接修复的寿命的关键因素,例如石皇冠.
- 选择水泥和边缘位置的选择可以显著影响密封能力和临床结果.
- 了解不同边缘接口的水泥行为对于优化恢复成功至关重要.
研究的目的:
- 为了比较各种生物活性和树脂水泥混凝土的石皇冠的微泄漏.
- 为了评估两个不同的边缘位置 (深度与升高) 对水泥微泄漏的影响.
- 为了确定水泥类型和边缘位置在密封效率上的相互作用.
主要方法:
- 在30个牙中准备了标准化的 mesial box 腔,并用树脂复合材料恢复.
- 牙被准备为合金皇冠,边缘放置在复合材料 (升高) 或在水泥面接口 (CEJ) (深) 下面的牙结构上.
- 用五种不同类型的水泥 (多级粘合树脂,自我粘合树脂,生物活性混合离子树脂,两种生物陶水泥) 凝固样本,并使用染料透来评估微漏.
主要成果:
- 在水泥类型和边缘位置 (p≤0.001) 之间发现了显著的相互作用.
- 在所有水泥集团中,高边缘始终显示微泄漏比深边缘少.
- 粘合树脂和生物活性混合水泥在两个边缘位置显示出最小的微泄漏,优于其他测试的水泥.
结论:
- 边缘位置显著影响微漏,高边缘提供更好的密封.
- 生物活性混合离子树脂和多阶段粘合树脂水泥为石修复提供了卓越的边际完整性.
- 临床建议应考虑水泥选择和战略边缘放置,以最大限度地减少微泄漏并提高恢复耐用性.
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