较长的光固化时间减少了老化对复合树脂硬度的影响,这种复合树脂用于根强化
Cleonice da Silveira Teixeira1, Filipe Colombo Vitali1, Eduardo Antunes Bortoluzzi2
1Department of Dentistry, Federal University of Santa Catarina, Florianopolis, Santa Catarina, Brazil.
概括
较长的光固化时间 (120s) 提高了复合树脂的硬度,以加强根,特别是在老化后. 较短的固化 (40s) 降低了硬度,特别是在长期储存后的顶部区域.
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
背景情况:
- 复合树脂对于加强牙根至关重要.
- 优化它们的特性,如硬度,对于长期的临床成功至关重要.
- 了解影响树脂性能的因素,如固化时间和老化,至关重要.
研究的目的:
- 为了评估用于根加强的复合树脂的硬度.
- 调查光固化时间,根管区和衰老对复合树脂硬度的影响.
- 为了确定最佳的固化参数,以提高机械性能.
主要方法:
- 20根切肢根用复合树脂增强,具有不同的光聚合时间 (40秒或120秒).
- 根被切成冠状,中部和顶部区域进行分析.
- 复合材料的硬度最初被测量,并在18个月的储水后,使用ANOVA和Tukey的测试进行分析.
主要成果:
- 光固化时间和根部都显著影响了复合材料的硬度.
- 由于储水而导致的老化也影响了硬度,并观察到显著的相互作用.
- 树脂硬度在顶峰地区始终较低.
- 在老化后,冠状和中间区域的硬度在40s固化时降低,但在120s固化时却没有降低.
结论:
- 延长光固化时间 (120秒) 提高了复合树脂的硬度,以加强根部,减轻与年龄相关的退化.
- 较短的固化时间 (40秒) 会导致硬度降低,特别是在顶根区域,并且更容易受到衰老的影响.
- 优化光固化协议对于保持内牙治疗牙中复合树脂的机械完整性至关重要.
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