Differences in Preparation Results of Two Reciprocal Ni-Ti Files with and Without Glide Path to the Changes on Root Canal Curvature

Background: Maintaining the anatomy of the root canal is crucial in root canal treatment. The super-elastic property of the nickel-titanium (Ni-Ti) file system provides advantages in preparation of curved root canals, as it can reduce the force on the root canal wall, increase centering ability, and reduce iatrogenic errors. Objective: The aim of this article is to determine the differences in preparation results of two reciprocal Ni-Ti files with and without glide path to the changes of root canal curvature. Materials and Methods: Twenty pieces of endodontic blocks (ISO# 15, 16 mm, 2% tapered) were divided into four randomly assigned groups. Group 1 (without glide path) and Group 2 (with glide path) were prepared with Wave One Gold (WOG). Group 3 (without glide path) and Group 4 (with glide path) were prepared with Reciproc Blue (RB). Each subject was explored using K-file #10. Glide path was prepared with ProGlider (PG) #16. Digital images of before and after the root canal preparations were taken using a digital camera with the same angle and distance settings. The before and after photos were superimposed on each other, and the transportation at the inner and outer root canal walls in the coronal curvature, apical curvature, and apical end points was measured with software. Results: No significant difference was found between changes in the coronal curvature using WOG and RB, with and without glide path (P > 0.05). The same result was observed between WOG and RB groups with glide path at each measurement point. Significant differences were found between changes in apical curvature and apical point in the inner wall using WOG and RB without glide path (P < 0.05). Conclusion: There were differences in root canal curvature prepared using WOG and RB on the apical region when prepared without glide path, but no differences were found when prepared with glide path at each point measurement.