Adıgüzel, MehmetYılmaz, Koray2024-09-192024-09-1920211300-9044https://doi.org/10.17567/ataunidfd.807472https://search.trdizin.gov.tr/tr/yayin/detay/423696https://hdl.handle.net/20.500.12483/15598Aim: The objective of this study was to compare the resistance to cyclic fatigue of One Curve (OC), 2Shape (TS), and Reciproc(RC) files by considering the operator’s experience.Materials and methods: Mesial root canals of ninety mandibular molar teeth were prepared by three endodontic residentsduring the first 6 months of their training (IE) or by three professionals with min. 5 years of endodontic training at postgraduatelevel (E). Then, 45 files used by the inexperienced group (IE-OC, IE-TS, and IE-RC), 45 files used by the experienced group (EOC, E-TS, and E-RC), and new 45 files (control group; C-OC, C-TS, and C-RC) were rotated in simulated canals until separationfailure occurred. (n=15) The time to fracture was calculated. For statistical analysis, ANOVA and Tukey’s post hoc tests wereused (P<0.05).Results: When compared to the experienced and inexperienced groups, the time-to-fracture of control group files was found tobe significantly higher (P<0.05). Comparing the experienced and inexperienced operator groups, no significant difference wasfound for RC files, whereas significant differences were determined for TS and OC files (P<0.05).Conclusions: The residual fatigue life of TS and OC instruments may be decreased by inexperienced operators more thanexperienced operators. Single file RC instrument was, however, not affected by the operator’s experience.eninfo:eu-repo/semantics/openAccessArticle311465110.17567/ataunidfd.807472423696