Ex-vivo Evaluation of the Torque Force on Periodontal Tissues During Endodontic Treatment

Objective: To examine the torque force generated on periodontal tissues by three dif-ferent Ni-Ti endodontic file systems during root canal preparation in freshly extracted teeth. Methods: Sixty single root teeth with an apical diameter corresponding to the size 15K-file were included to this study. Three experimental groups (n=20) were arranged. After establishing the working length teeth were placed on a digital torque-meter via self-curring polymethylmetacrylate adaptor. Thereafter, the following Ni-Ti file systems were tested: WaveOne Primary File (WO), WaveOne Gold Primary file (WOG) and size 25 OneShape (OS). In all groups, canals were prepared with the manufacturers’ recommendations. The values measured with the torque meter were recorded. Results: There was no statistical difference at WO-WOG groups comparisons (p>0.05). However, there were statistical differences at WO–OS and WOG–OS groups compa-risons (p<0.016). The minimum torque value was at OS Group (2.0 Ncm) while maximum torque value was at WO Group (5 Ncm). Conclusion: The results of this study showed that torque forces generated with re-ciproc files were significantly higher than that of Ni-Ti rotary file. Further we can speculate that elimination of the periodontal inflammation-borne tooth mobility by phase I periodontal therapy before endodontic treatment can reduce the risk of damage caused by rotational forces during endodontic treatment.