Remaining endodontic filling material was observed on the canal walls of all teeth regardless of the technique used. Hand files combined with Gates-Glidden burs (group I) and the reciprocating technique (group III) removed more filling material from the canal walls than the Mtwo R files. The reciprocating technique was the most rapid method for removing gutta-percha and sealer, followed by the rotary technique and the hand file technique.

Silva EJNL, Belladonna FG, Zuolo AS, Rodrigues E, Ehrhardt IC, Souza EM, De-Deus G. Effectiveness of XP-endo Finisher and XP-endo Finisher R in removing root filling remnants: a micro-CT study. International Endodontic Journal, 51, 86-91, 2018. Aim To evaluate the efficacy of filling material removal from oval-shaped canals after the use of supplementary files (XP-endo Finisher and XP-endo Finisher R) through microcomputed tomographic (micro-CT) analysis. Methodology The root canals of twenty maxillary single-rooted teeth were prepared with Reciproc R25 files and filled with gutta-percha and AH Plus sealer using the continuous wave of condensation technique. The root canals were then retreated using Reciproc R25 and R40 instruments. After this, the specimens were assigned to two groups according to the supplementary cleaning approach, using XP-endo Finisher and XP-endo Finisher R. The surface area and volume of removed filling material was assessed using micro-CT imaging before and after the use of the XP-endo instruments. Data were analysed statistically with a significance level of 5%. Results Removal of filling material at 66.8% and 59.4% in volume and 67.3% and 61.4% in surface area was seen for the XP-endo Finisher and the XPendo Finisher R files, respectively. The amount of filling material removed by both supplementary files was highly significant (P = 0.000). No significant difference in the percentage of removed filling material was detected for the XP-endo instruments (P = 0.636 for volume and P = 0.667 for surface area). Conclusions Both XP-endo files were equally effective in the removal of remaining filling material from straight oval-shaped canals. None of the instruments were able to remove all the residual filling material.

AimTo evaluate the performance of XP‐endo Finisher R instruments when removing root filling remnants from oval‐shaped canals using microcomputed tomographic (micro‐CT) imaging as the analytical tool. Passive ultrasonic irrigation (PUI) was used as a reference technique for comparison.MethodologyTwenty mandibular incisors with oval‐shaped canals were matched based on similar anatomic features of the canal (volume, aspect ratio and 3D configuration) after scanning procedures. The canals were prepared with Reciproc R25 instruments, filled with gutta‐percha and AH Plus sealer using the single‐cone technique and retreated up to a Reciproc R40 instrument. After retreatment procedures, the specimens were rescanned, and the homogeneity between the specimens, the oval‐shaped anatomy and the remaining filling material were confirmed. The pair‐matched samples were assigned to two experimental groups (n = 10), according to the supplementary approach used: XP‐endo Finisher R or PUI. Each sample was scanned after each endodontic procedure. The volume of remaining root filling material was quantified before and after the use of each supplementary approach. This analysis was performed considering the total canal (Student t‐test) and also by thirds (anova procedure followed by a Bonferroni correction). Data were analysed statistically with a significance level of 5%.ResultsThe volume of root filling material at baseline was similar between the groups (t‐test, P = 0.787). XP‐endo Finisher R removed significantly more root filling material compared to PUI (t‐test, P = 0.015), as it removed a mean of ≅32% material compared to 12% for the PUI. There was no difference in the amount of root filling material removed in the root canal thirds after using both supplementary approaches (one‐way anova, P = 0.07 for XP‐endo Finisher R and P = 0.886 for PUI).ConclusionsBoth supplementary approaches significantly reduced the volume of remaining root filling material from oval‐shaped canals. The XP‐endo Finisher R instrument removed significantly more root filling material than PUI. None of the supplementary approaches was able to render oval‐shaped canals completely free from remaining root filling material.

Both M-Wire Reciproc and Reciproc Blue instruments were effective in removing filling materials from oval-shaped straight canals. Apical patency was reestablished in all specimens.