Abstract
BACKGROUND: Residual root canal filling material might inhibit the efficacy of irrigation materials, medicaments and sealers during the endodontic non-surgical retreatment. The aim of this study was to compare the efficacy of the XP Endo Retreatment file with other retreatment systems on removing the root canal filling materials by using Micro-CT during the endodontic retreatment. METHODS: Sixty human mandibular molars with mesial root curvature between 20° and 40° were included in the study. Mesiobuccal canals of specimens were prepared with the ProTaper Next file and filled with gutta percha and AH Plus sealer. Samples were scanned with Micro-CT and they were randomly divided into 5 experimental groups. Root canal treatments were removed with the following systems. Group PTUR: Root canal filling was removed using ProTaper Universal Retreatment System. Group Rec25: Reciproc R25 file was used to remove the root canal filling. Group RE: Retreatment of specimens were performed using R-Endo Retreatment System. Group XPER: Root canal filling was removed using XP Endo Retreatment System. Group HF: Hand files and Gates Glidden burs was used to remove the root canal filling. The time (second) from the use of the first file to reach the WL (T1) and the time (second) to remove all obturation material (T2) were recorded. Micro-CT images were obtained from the samples after removing the root canal filling and the volume of the residual root canal filling was calculated. The data was statistically analyzed (P < 0.05). RESULTS: The residual root canal filling volume and the percentage of residual root canal filling material (%) in the RE and Rec25 groups were statistically higher than the PTUR, XPER, and HF groups. T1 and T2 values were the highest in the HF and time values were the lowest in the XPER. CONCLUSIONS: According to the results of this study, all tested methods could not completely remove filling material from the root canal. PTUR, XPER, and HF removed the root canal filling more efficiently than Rec25, and RE. It was concluded that the XP-Endo group was the fastest retreatment system among the tested groups.