Abuhulaibah Hind F, AbuMostafa Ammar
Restorative Dentistry Department, Endodontics Division, Riyadh Elm University, Riyadh, Saudi Arabia.
Int J Dent. 2020 Sep 19;2020:8830163. doi: 10.1155/2020/8830163. eCollection 2020.
Forty-five files from each brand were randomly assigned to three groups ( = 15) and subjected to the following: no immersion (control), 1-minute immersion, and 5-minute immersion in 2.5% NaOCl at 37°C. CF for all the files was tested within a well-lubricated stainless-steel artificial canal in a water bath at 37°C simulating body temperature. The procedure was video recorded, and the number of cycles to fracture (NCF) was calculated by multiplying the time taken to fracture, with the number of rotations per second. The data were analyzed for normality, and thereafter, one-way ANOVA with multiple Bonferroni was used as the post hoc test.
The resistance to CF of OC files was significantly higher than PTG files in all groups. In groups immersed in NaOCl for one minute, OC files showed significant drop in the CF resistance; PTG files showed a drop as well but not significantly. Both files demonstrated a significant drop in resistance to CF after immersion in NaOCl for five minutes compared to the control group.
OC files were significantly more resistant to CF compared to PTG in all groups. Immersion in 2.5% NaOCl for 5 minutes significantly reduced the resistance to CF for all the files.
每个品牌的45根锉随机分为三组（每组 = 15根），并进行以下处理：不浸泡（对照组）、在37°C的2.5%次氯酸钠中浸泡1分钟和浸泡5分钟。所有锉的循环疲劳（CF）在模拟体温的37°C水浴中一个润滑良好的不锈钢人工根管内进行测试。该过程进行视频记录，断裂循环次数（NCF）通过将断裂所需时间乘以每秒旋转次数来计算。对数据进行正态性分析，然后使用带有多重Bonferroni检验的单因素方差分析作为事后检验。
在所有组中，OC锉的CF抗力显著高于PTG锉。在次氯酸钠中浸泡1分钟的组中，OC锉的CF抗力显著下降；PTG锉也有下降，但不显著。与对照组相比，两种锉在次氯酸钠中浸泡5分钟后CF抗力均显著下降。
在所有组中，OC锉对CF的抗力显著高于PTG锉。在2.5%次氯酸钠中浸泡5分钟显著降低了所有锉的CF抗力。
