Cyclic Fatigue Resistance of Three Glide-path File Systems in Double-curvature Simulated Canals: An in Vitro Study

To compare the cyclic fatigue resistance of three rotary glide-path file systems (ProGlider, Px-One, and Pro-path) in simulated canals with double curvature.

A total of 78 new files (n=26 per system) were evaluated and divided into six groups according to canal curvature (30^° and 60^°). Artificial stainless-steel canals (19 mm long, 8 mm curvature radius) were used. All files were operated at 300 rpm and 2.0 Ncm torque using continuous rotation at room temperature (22±2 ^°C). Cyclic fatigue resistance was assessed by recording the time to fracture. Shapiro-Wilk and Levene's tests were performed to evaluate normality and homogeneity of variance, respectively. Data were analyzed using Welch's ANOVA and Games-Howell post hoc test (P<0.05).

The Pro-path system showed significantly greater fatigue resistance than Px-One and ProGlider at both 30^° and 60^° canal curvatures (P<0.001). In 30^° canals, Pro-path exhibited a mean fracture time of 76.42±12.50 min, compared to 57.41±11.77 min for ProGlider and 49.84±14.77 min for Px-One. In 60^° canals, Pro-path again demonstrated superior performance (18.90±4.86 min), followed by ProGlider (5.71±1.23 min) and Px-One (4.70±1.20 min).

these experimental conditions, Pro-path demonstrated significantly greater cyclic fatigue resistance than ProGlider and Px-One in double-curvature simulated canals. However, the absence of body temperature control and a static testing model limits clinical extrapolation. Further studies validating these findings under physiological conditions and dynamic kinematics are warranted.