en Oral medicine Oral medicine Original article Original article <div> <table align="center" hspace="0" vspace="0"> <tbody> <tr> <td style="padding: 0in 12px; text-align: justify;" valign="top"><span style="font-size:13pt"><span new="" roman="" style="font-family:" times=""><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">Background and Aim</span></span></span></b><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">:</span></span></span></b><b> </b><span style="font-size:9.0pt"><span style="font-family:" verdana="">Complete removal of gutta-percha from the root canal system and its remnants is a challenge in endodontic retreatment. This ex-vivo study aimed to assess the efficacy of XP-Endo Finisher R (XEFR) in removing root filling remnants from straight canals of mandibular premolars in root canal retreatment. &nbsp;</span></span></span></span><br> <span style="font-size:13pt"><span new="" roman="" style="font-family:" times=""><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">Materials and Methods:</span></span></span></b><span style="font-size:9.0pt"><span style="font-family:" verdana=""> In this ex-vivo study, 30 single-rooted mandibular premolars with straight roots were selected. The root canals were instrumented and filled. Retreatment was then performed using D RaCe system. Teeth were then randomized into two groups of A and B (n=15). In group A, root canal retreatment was completed with XEFR. In group B, XEFR was not used. To evaluate the filling material remnants, the roots were split into halves and assessed under a stereomicroscope and photographed. The amount of remaining gutta-percha in the coronal, middle and apical thirds of the roots was measured by AUTOCAD software and analyzed with two-way ANOVA.</span></span></span></span><br> <span style="font-size:13pt"><span new="" roman="" style="font-family:" times=""><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">Results</span></span></span></b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">:</span></span></span><span style="font-size:9.0pt"><span style="font-family:" verdana=""> The amount of residual filling material was significantly lower in the coronal, middle and apical thirds and the entire root length in XEFR group (P<0.001).</span></span></span></span><br> <span style="font-size:13pt"><span new="" roman="" style="font-family:" times=""><b><span style="font-size:9.0pt"><span style="font-family:" verdana=""><span style="color:#2e74b5">Conclusion:</span></span></span></b> &nbsp;<span style="font-size:9.0pt"><span style="font-family:" verdana="">Use of XEFR significantly decreased the residual root filling material in the root canals. </span></span></span></span></td> </tr> </tbody> </table> </div> Gutta-Percha, Root Canal Filling Material, Root Canal Therapy 142 147 http://jrdms.dentaliau.ac.ir/browse.php?a_code=A-10-858-1&slc_lang=en&sid=1 P Amooyan 75.parya@gmail.com 100319475328460010466 100319475328460010466 No Private Dentistry Practice, Tehran, Iran H Akhavan hengamehakhavan@yahoo.com 100319475328460010467 100319475328460010467 No Department of Endodontics, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran E Esnaashari ehsan_dmd@yahoo.com 100319475328460010468 100319475328460010468 Yes Department of Endodontics, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran