Evaluation of Time to Fracture and Vertical Forces Applied by a Novel Gentlefile System for Root Canal Preparation in Simulated Root Canals

• A new stainless steel file, the Gentlefile, was examined.
• A novel system was used to assess vertical force applied by the file on the canal.
• The Gentlefile showed significantly better resistance to cyclic fatigue.
• The Gentlefile applied significantly less vertical force on the canals.

IntroductionA great number of studies performed in the last 3 decades have shown the superior mechanical features of nickel-titanium files as compared with stainless steel files. A novel file system recently developed, Gentlefile, defies these findings and claims to have superior qualities despite the fact it is made from stainless steel.MethodsThree file systems were used in this experiment: ProTaper Next (X1, X2, and X3), RevoS (SC2, SC3, and AS30), and Gentlefile (GF1, GF2, and GF3). Time to fracture, rotations to fracture, and vertical forces applied to a simulated root canal, which was fabricated from a metal block with a Plexiglas cover, were measured.ResultsThe GF system required significantly longer time and more rotations to fracture compared with the ProTaper and RevoS systems (P < .001). The GF system applied significantly less vertical force to the canal in comparison with the ProTaper and RevoS systems (P < .01).ConclusionsUnder the limitations of this study the GF system showed better mechanical properties in comparison with the ProTaper and RevoS systems. Further investigation is needed to assess the clinical meaning of these findings.