Instrumentation time and effectiveness of hand and rotary files in a prototyped second mandibular primary molar: A micro‐CT study

Background Eccentric instruments have been proposed as more effective and less time‐consuming for endodontic instrumentation. Aim To compare biomechanical outcomes of different instrumentation systems and time undertaken for instrumentation in resin prototypes. Design Sixty standardized prototypes of mandibular second primary molars were instrumented according to the following systems: K‐files, ProTaper Next (PTN), XP‐endo Shaper (XPS), XP‐endo Finisher (XPF), XP–Clean (XPC), and Sequence Baby File (SBF; n = 10/each). Irrigation was performed with saline with simultaneous aspiration, and time spent was recorded. The prototypes were micro‐CT‐scanned before and after the instrumentation, and image sets were reconstructed and registered. Non‐instrumented areas, accumulated debris, removed root material volume, and canal transportation were quantified. Data were analyzed through ANOVA, the Kruskal–Wallis test, and the Wilcoxon signed‐rank test (α = 5%). Results K‐files and SBF resulted in more instrumentation time (p