牙科水泥应用在内冠和内置修复上的有限元应力分析
Satrio Wicaksono1, Wandi Prasetia1, Anna Muryani2
1Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Bandung, West Java, Indonesia.
概括
树脂水泥的选择显著地影响了onlay修复中的应力分布,而光固化水泥提供了更大的应力降低. 然而,由于其优越的结合强度,建议在内冠和内置修复中使用双固化树脂水泥.
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
- 计算式牙科 计算式牙科
背景情况:
- 内冠牙和内冠牙是间接修复,用于修复严重损坏的后牙.
- 树脂水泥的选择对于这些修复的寿命和成功至关重要.
- 在各种负载条件下了解不同树脂水泥的机械行为对于临床决策至关重要.
研究的目的:
- 为了评估不同类型的树脂水泥对牙内应力分布的影响,用内冠和在线涂层恢复牙.
- 在模拟的牙科修复中,比较光固化与双固化树脂水泥的机械性能.
主要方法:
- 使用微型CT扫描了第一个牙,以创建用于计算模拟的3D模型.
- 模拟了八种模型,不同的修复类型 (onlay,endocrown),水泥类型 (光固化,双固化树脂水泥) 和负载条件 (垂直和斜负载).
- 用有限元分析分析了模拟的闭合力下的应力分布.
主要成果:
- 与双重固化树脂水泥相比,在使用光固化树脂水泥时,经过onlay修复的牙表现出显著的应力降低 (高达70%).
- 相反,树脂水泥类型没有影响用内冠修复的牙的应力分布.
- 与轻度固化树脂水泥相比,双固化树脂水泥表现出优越的结合强度.
结论:
- 由于其增强的结合强度,双固化树脂水泥被推用于内冠和内置修复.
- 机械行为和应力分布依赖于恢复,在线层对水泥类型表现出敏感性.
- 对材料特性和临床性能进行进一步的研究是有必要的.
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