Background: Endodontic retreatment has become a routine procedure in modern dentistry. Retreatment procedures often result in extrusion of debris through the apex and into the periradicular tissues, which may lead to post-operative pain and inflammation. Thus, investigating the effect of instrumentation protocols on the amount of extruded debris is important. Endodontists often must resort to supplementary techniques after retreatment to enhance canal cleaning. Therefore, the present study investigated the amount of extruded debris by a novel supplementary file. Aim of the study: To evaluate the amount of apically extruded debris during retreatment using Reciproc R40 compared to that extruded by Reciproc R40 followed by supplementary instrumentation using XP-endo Finisher R. Materials and Methods: Eighteen single-rooted, single-canalled mandibular premolars were instrumented with RaCe EVO rotary system and obturated using gutta-percha and bioceramic sealer. Specimens were then randomly assigned to one of two groups according to the retreatment method (n=9): Group 1: Reciproc R40, Group 2: Reciproc R40 + XP-endo Finisher R. Pre-weighed Eppendorf tubes were fixed to the specimens to collect the apically extruded debris. The dry weight of extruded debris was then calculated. Results: All groups were associated with debris extrusion with no significant differences. Conclusions: XP-endo Finisher R used as a supplementary file for enhancing retreatment of oval-shaped canals had no significant effect on the amount of apically extruded debris.