预热对复合树脂粘度的影响
Déborah Lousan do Nascimento Poubel1, Raquel Cardoso da Silva1, Ana Paula Dias Ribeiro2
1Department of Dentistry, University of Brasilia, Brasilia, Federal, Brazil.
Journal of conservative dentistry and endodontics
|May 23, 2024
概括
预热牙科复合树脂显著降低粘度,温度是主要因素. 粘度随着温度的提高而降低,但树脂在从热中去除后迅速冷却.
科学领域:
- 牙科材料科学 牙科材料科学
- 聚合物化学 聚合物化学
背景情况:
- 预热牙科复合树脂是一种具有潜在临床益处的技术.
- 了解时间和温度对树脂粘度的影响对于有效应用至关重要.
研究的目的:
- 研究预热时间和温度对复合树脂粘度的影响.
- 为了确定温度变化和牙科复合材料粘度降低之间的关系.
主要方法:
- 十一个复合树脂被加热到60°C,并被监测到冷却到25°C.
- 使用在不同温度 (25°C,35°C,50°C,60°C) 的振荡剪切试验测量粘度.
- 统计分析包括单向和双向ANOVA.
主要成果:
- 时间显著影响粘度 (P < 0.0001),可见变化长达 6 分钟.
- 温度升高显著降低了复合树脂粘度 (P < 0.05).
- 像Palfique LX5这样的特定树脂显示,随着温度的增加,粘度的减少更大.
结论:
- 10分钟的预热有效地减少了至少84%的粘度.
- 复合树脂从热中取出后5分钟内冷却到室温.
- 需要进一步的研究来优化临床使用的预热协议.
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