Effects of Preparation with The Self-Adjusting File, TRUShape and XP-Endo Shaper Systems, and a Supplementary Step with XP-Endo Finisher R on Filling Material Removal During Retreatment of Mandibular Molar Canals

A.G. Machado, B.P.S. Guilherme, J.C. Provenzano, M.F. Marceliano-Alves, L.S. Gonçalves, J.F. Siqueira Jr, M.A.S. Neves

International Endodontic Journal. 2018 Nov 12 [Epub ahead of print]

  

AIM: To compare the effects of three instrumentation systems, and a supplementary approach with a finishing instrument, on filling material removal during retreatment of mandibular molar canals.

METHODS: Sixty mesial canals from mandibular molars (Vertucci's type IV anatomy) were instrumented, filled and subjected to retreatment. After initial removal of the root canal filling material using the D-RaCe system, the canals were randomly distributed into 3 groups (n=20) according to the instrument system used for preparation: the Self-Adjusting File (SAF), TRUShape or XP-endo Shaper. The filling material volume in the apical 5 mm of the canals was assessed by means of micro-computed tomography (micro-CT) before and after retreatment. All specimens with residual filling material were subjected to a supplementary approach with the XP-endo Finisher R instrument and another micro-CT scan was taken. Data on the volumes of filling material and incidence of total removal were compared between groups by the general linear model for paired data and the Fisher's exact test. The effects of the refinement step were evaluated by the Wilcoxon Signed Ranks test.

RESULTS: The amount of removed material was 92.4%, 96.9% and 96.9% for the SAF, TRUShape and XP-endo Shaper, respectively. There were no significant differences between them (p>0.05). Canals were completely cleaned of filling material in 70% of the specimens for XP-endo Shaper, 55% for SAF and 30% for TRUShape; the difference between XP-endo Shaper and TRUShape was significant (p=0.03). The supplementary step with the XP-endo Finisher R instrument was associated with additional filling material removal of 38% (p<0.001). Six more canals were rendered free of filling material after using this finishing instrument.

CONCLUSIONS: The tested systems were equally effective in removing the mass of filling material from the apical 5 mm of molar canals. The supplementary step with the XP-endo Finisher R instrument enhanced filling material removal.

 

Additional Info

  • ReDent Nova’s note:

    The three instruments that were tested (XP-Endo Shaper, TRUshape, SAF System) showed similar results, probably because the protocol did not follow the recommendations for retreatment with the Self-Adjusting File System. The integration of chloroform is likely to improve the retreatment results significantly, as shown in previous researches.

    Another aspect that was disregarded in this case is the residual dentin thickness. Previous researches showed that the rotary instruments examined in this research tend to over-instrument the canals, remove a lot of sound dentin and risk the survival of the tooth, while the SAF System preserves sound dentin and follows the root canal morphology.

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  • View abstract on PubMed. PMID: 30417931