Impact of Reduced Irrigation and Preparation Time on the Shaping Efficiency of the New SAF Infinitum System in Long Oval Root Canals.

Abstract

Introduction: This study aimed to evaluate the impact of reduced irrigation and preparation time on the shaping efficiency of the new Self-Adjusting File (SAF) Infinitum system in long oval root canals.

Methods: Thirty-six extracted mandibular canines with long oval canals were anatomically matched using micro-computed tomography analysis and assigned to three experimental groups (n = 12) according to the irrigation protocol: (1) 2.5% NaOCl (4 minutes at 4 mL/min); (2) 2.5% NaOCl + etidronate (4 minutes at 2 mL/min); and (3) 2.5% NaOCl + etidronate (2 minutes at 2 mL/min). Root canals were prepared using a 2.0-mm SAF Infinitum instrument under continuous irrigation. Pre- and postoperative micro-computed tomography scans were used to assess canal volume (mm³), surface area (mm²), and the percentage of unprepared canal walls. Data were analyzed using 1-way ANOVA (α = 5%).

Results: All preparation protocols increased canal volume (26.4%-32.4%) and surface area (5.3%-8.9%), with no significant differences among groups (P > .05). The extent of unprepared canal walls remained comparable across groups, with mean values ranging from 8.7%-14.7% (P > .05). No significant shaping errors were observed, and no instrument fracture occurred during the preparation procedures. Superimposed color-coded surface models confirmed uniform dentin removal around the canal perimeter.

Conclusions: All tested protocols yielded comparable shaping performance. Reducing SAF preparation from 4 minutes-2 minutes using NaOCl or etidronate mixture did not compromise the preparation of long oval canals, achieving comparable increases in volume and surface area while preserving a similar extent of unprepared canal walls.