Correlative Bacteriologic and Micro-Computed Tomographic Analysis of Mandibular Molar Mesial Canals Prepared by Self-Adjusting File, Reciproc, and Twisted File Systems

J. F. Siqueira Jr, F. R. Alves, M. A. Versiani, I. N. Rôças, B. M. Almeida, M. A. Neves, and M. D. Sousa-Neto

Journal of Endodontics. 2013 August; 39(8):1044-50.


INTRODUCTION: This ex vivo study evaluated the disinfecting and shaping ability of 3 protocols used in the preparation of mesial root canals of mandibular molars by means of correlative bacteriologic and micro-computed tomographic (μCT) analysis.

METHODS: The mesial canals of extracted mandibular molars were contaminated with Enterococcus faecalis for 30 days and assigned to 3 groups based on their anatomic configuration as determined by μCT analysis according to the preparation technique (Self-Adjusting File [ReDent-Nova, Ra'anana, Israel], Reciproc [VDW, Munich, Germany], and Twisted File [SybronEndo, Orange, CA]). In all groups, 2.5% NaOCl was the irrigant. Canal samples were taken before (S1) and after instrumentation (S2), and bacterial quantification was performed using culture. Next, mesial roots were subjected to additional μCT analysis in order to evaluate shaping of the canals.

RESULTS: All instrumentation protocols promoted a highly significant intracanal bacterial reduction (P < .001). Intergroup quantitative and qualitative comparisons disclosed no significant differences between groups (P > .05). As for shaping, no statistical difference was observed between the techniques regarding the mean percentage of volume increase, the surface area increase, the unprepared surface area, and the relative unprepared surface area (P > .05). Correlative analysis showed no statistically significant relationship between bacterial reduction and the mean percentage increase of the analyzed parameters (P > .05).

CONCLUSIONS: The 3 instrumentation systems have similar disinfecting and shaping performance in the preparation of mesial canals of mandibular molars.


The full article is available online: ResearchGate

siqueira microCT joe 2013


Additional Info

  • ReDent Nova’s note:


    The small sample size (n=10) and the variability within the sample (roots with and without an isthmus) may have not allowed to demonstrate the superiority of disinfection by the SAF system that was demonstrated in 3 previous studies by the same group. Additionally, SAF was operated for only 3 minutes with irrigation flow rate of 2mL/min – both factors non-compliant with the clinical guidelines of the system, and is likely to lead to insufficient cleaning.

  • publisher: publisher
  • View abstract on PubMed. PMID: 23880274