三种当代牙科聚合物的冠状失效负荷与屈曲强度的关系
1Department of Substitutive Dental Sciences, Taibah University, Madinah 42353, Saudi Arabia.
Polymers
|November 14, 2023
概括
柔性强度测试不能预测聚合物牙冠的临床性能. 牙医不应该依赖制造商报告的屈曲强度数据来预测临床使用中的冠状失效负荷.
科学领域:
- 生物材料科学 生物材料科学
- 牙科材料科学 牙科材料科学
- 聚合物科学 聚合物科学
背景情况:
- 聚合物材料越来越多地用于牙科修复,包括牙冠.
- 制造商提供基于标准化测试的屈曲强度数据.
- 屈曲强度对临床皇冠性能的可预测性仍然不清楚.
研究的目的:
- 为了确定通过三点曲 (3PB) 测量的屈曲强度是否可以预测聚合物牙冠的故障负载,使用冠 (CTC) 试验.
- 为了比较三个聚合物品牌的性能:Trilor,Juvora和Pekkton.
主要方法:
- 来自Trilor,Juvora和Pekkton的制聚合物条和冠.
- 使用DSC,FTIR和燃烧测试进行材料特征测试.
- 在3PB中测试了曲强度的条,在CTC中测试了在树脂支柱上接后的故障负载的冠.
- 使用ANOVA,皮尔森相关性和回归分析分析数据;用SEM特征骨折.
主要成果:
- 在平均冠状失效负荷 (Trilor > Juvora > Pekkton) 和平均屈曲强度 (Trilor > Juvora = Pekkton) 中存在显著差异.
- 在不同材料 (变形,柔性到脆性,组合) 之间,断裂模式各不相同.
- 柔性强度与任何材料的皇冠故障负载都没有相关性.
结论:
- 根据3PB测试确定的屈曲强度不是聚合物牙冠故障负载的可靠预测指标.
- 牙医应谨慎使用制造商报告的屈曲强度数据来评估临床性能.
- 需要进一步的研究来确定聚合物牙科材料临床性能的可靠预测指标.
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