在平面上或不平面? 通过全面的多方法调查,探索平面设计对旋转仪器的影响
Emmanuel J N L Silva1,2,3, Murilo P Alcalde4, Jorge N R Martins5,6,7
1Department of Endodontics, Fluminense Federal University, Rio de Janeiro, Brazil.
International endodontic journal
|August 18, 2023
概括
一种新的平面-旋转仪表显示了较好的切割能力,但与其非平面对应器相比,它具有较低的断裂阻力. 金和机械性能不同,影响了根管制备中的性能.
科学领域:
- 牙周内科医院 牙周内科医院 牙周内科医院
- 材料科学 材料科学 材料科学
- 生物材料是一种生物材料.
背景情况:
- - (NiTi) 旋转仪器在内牙科中至关重要.
- 仪器设计显著影响机械性能和临床性能.
- 评估像平面边形几何学这样的新设计对于改善根管道准备至关重要.
研究的目的:
- 评估平面设计对新型NiTi旋转仪器的几何,金,机械性能和成型能力的影响.
- 为了比较平面仪器与其非平面仪器原型.
主要方法:
- 测试了65个平面和65个非平面NiTi旋转仪器 (25/.04).
- 评估了几何,NiTi比率,相变换温度和机械性能 (时间/周期到断裂,扭矩,曲,曲).
- 评估切割能力和运河准备,使用下牙的微型CT成像.
主要成果:
- 平面仪表表现出优越的切割能力,但时间,旋转和扭矩到断裂显著降低.
- 在平面仪器中发现了表面均性和横截面形状的不一致性.
- 阶段转换温度不同,而NiTi比率,旋转角度,曲和曲强度是可比的.
- 没有观察到准备时间,未触及的运河壁,碎片量或牙厚度减少的显著差异.
结论:
- 平面NiTi仪器提供了更高的切割效率,但降低了断裂阻力.
- 设计变化会影响金性能,特别是相变换温度.
- 尽管切割和断裂阻力有差异,但平面和非平面设计的整体通道制备效率与平面设计相似.
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