Does experience matter? Evaluating canal preparation time in straight and curved canals

ABSTRACT Aim: Evaluate the influence of operator experience on glide path and root canal preparation times using three nickel-titanium systems across different preparation philosophies, in both straight and curved canals: A rotary system with variable taper, ProTaper Gold ® , a rotary system with constant taper, EndoGal ® , and a single-file reciprocating system, WaveOne Gold ® . Methods: Sixty straight and 60 curved canals were prepared by one experienced and one non-experienced operator following manufacturers’ protocols. Each operator prepared one group ( n = 10) of straight canals and one group ( n = 10) of curved canals, with each system, in a total of six groups by each operator. Instrumentation time was recorded using a digital stopwatch, which measured only the active time of file rotation inside the canal. Results: Glide path preparation times differed significantly among systems and between operators ( P < 0.001). During root canal preparation, WaveOne Gold® exhibited the shortest preparation times (13.2–23.7 s) and the lowest operator-dependent variability, with no significant differences between operators in straight canals ( P > 0.05). ProTaper Gold ® required the longest preparation times (39.1–87.3 s) and showed the greatest operator-related variability, while EndoGal® demonstrated intermediate performance (24.1–54.9 s). Conclusions: These findings, consistent with the existing literature, suggest that reciprocating single-file systems may improve procedural efficiency and reduce technique sensitivity, making them particularly suitable for novice operators in controlled clinical settings such as undergraduate dental clinics, supporting the inclusion of rotary and reciprocating instruments in undergraduate endodontic curricula.