Al-Hadlaq Solaiman M
Department of Restorative Dental Sciences, Division of Endodontics, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
Aust Endod J. 2013 Aug;39(2):62-5. doi: 10.1111/j.1747-4477.2010.00290.x. Epub 2011 Feb 20.
Twisted files (TFs) are rotary nickel-titanium (NiTi) instruments that are produced with a newly developed manufacturing process that is supposed to improve their properties, especially flexibility and resistance to cyclic flexural fatigue failure. The aim of this study was to study the cyclic flexural fatigue failure resistance of tip size International Standards Organization 25 TFs with two tapers 0.04 and 0.06 and to compare them with the Profile (PF) rotary NiTi files of similar tip size and taper. Four groups of fifteen files were used in this study. TF (25/0.04), TF (25/0.06), PF (25/0.04) and PF (25/0.06) were tested using the cyclic flexural fatigue testing device. The time to failure during cyclic flexural fatigue testing was recorded. The mean time required for the instrument to fail under cyclic flexural fatigue testing was 235.5 ± 68 s for 25/0.04 TF, 188.5 ± 75 s for 25/0.06 TF, 180.3 ± 102 s for 25/0.04 PF and 156.3 ± 17 s for 25/0.06 PF. The difference between the time to failure of 25/0.04 TF and 25/0.06 TF was not statistically significant. The difference between the time to failure of TF and PF of similar tip size and taper was not statistically significant. The findings of this study indicate that size 25/0.04 and 25/0.06 TFs had similar resistance to cyclic flexural fatigue failure. In addition, TFs were not superior, in terms of resistance to cyclic flexural fatigue failure, to PF of similar tip size and taper.
扭转锉（TFs）是旋转镍钛（NiTi）器械，采用新开发的制造工艺生产，该工艺旨在改善其性能，尤其是柔韧性和抗循环弯曲疲劳破坏的能力。本研究的目的是研究尖端尺寸为国际标准组织25号、锥度分别为0.04和0.06的TFs的抗循环弯曲疲劳破坏能力，并将其与类似尖端尺寸和锥度的Profile（PF）旋转NiTi锉进行比较。本研究使用了四组，每组十五根锉。使用循环弯曲疲劳测试装置对TF（25/0.04）、TF（25/0.06）、PF（25/0.04）和PF（25/0.06）进行测试。记录循环弯曲疲劳测试过程中的失效时间。在循环弯曲疲劳测试下器械失效所需的平均时间，25/0.04 TF为235.5±68秒，25/0.06 TF为188.5±75秒，25/0.04 PF为180.3±102秒，25/0.06 PF为156.3±17秒。25/0.04 TF和25/0.06 TF的失效时间差异无统计学意义。类似尖端尺寸和锥度的TF和PF的失效时间差异无统计学意义。本研究结果表明，25/0.04和25/0.06尺寸的TFs具有相似的抗循环弯曲疲劳破坏能力。此外，在抗循环弯曲疲劳破坏方面，TFs并不优于类似尖端尺寸和锥度的PF。
