The Efficacy of Rotary, Reciprocating, and Combined Non-Surgical Endodontic Retreatment Techniques in RemovingaCarrier-BasedRootCanalFillingMaterial from Straight Root Canal Systems: A Micro-Computed To
• The aim of this study is to analyze and compare the ecacy of three non-surgical endodontic
retreatment techniques in removing a carrier-based root canal filling material from straight root canal
systems.
The study was performed on 99 single-rooted extracted teeth using the ProTaper Gold
endodontic rotary system up to the F2 file (Dentsply Maillefer, Baillagues, Switzerland), which were
sealed with GuttaCore (Dentsply Maillefer, Ballaigues, Switzerland) and AH plus epoxy resin
sealer (Dentsply DeTrey, Konstanz, Germany) and randomly assigned to the following non-surgical
retreatment.
• Techniques: ProTaper Retreatment endodontic rotary instruments (D1–D3 files, Dentsply
Maillefer, Ballaigues, Switzerland; n = 33, PTR), Reciproc Blue endodontic reciprocating instrument
(R50, VDW, Munich, Germany; n = 33, RCB50), and a combined root canal retreatment technique
between Gates-Glidden drills (sizes #3 and #2, Dentsply Maillefer, Ballaigues, Switzerland) and
Hedstrom files (file size 35, 30, and 25, Dentsply Maillefer, Ballaigues, Switzerland; n = 33; H-GG).
All of the teeth were submitted twice to a micro-computed tomography (micro-CT) scan, before
and after non-surgical endodontic retreatment procedures.
The volume of root canal filling material (mm3), volume of remaining root canal filling material (mm3), non-surgical endodontic retreatment
working time (min), proportion of remaining root canal filling material (%), and ecacy of root canal
filling material removal between the non-surgical endodontic retreatment techniques were analyzed
using ANOVA one-way statistical analysis.
Statistically significant di erences were observed between the proportions of remaining root canal filling material of PTR and H-GG (p = 0.018), between the
non-surgical endodontic retreatment working times (min; p < 0.001), and between the ecacies of
root canal filling material removal by the non-surgical endodontic retreatment techniques (p = 0.009).
However, the non-surgical endodontic retreatment systems allow for similar carrier-based root canal
filling material removal.
