Tabriz University of Medical Sciences Journal of Dental Research, Dental Clinics, Dental Prospects 2008-210X 12 4 2018 12 26 Apically extruded debris and irrigants during root canal filling material removal using Reciproc Blue, WaveOne Gold, R-Endo and ProTaper Next systems 272 276 10.15171/joddd.2018.042 EN Cangul Keskin Evren Sarıyılmaz Journal Article 10.15171/joddd.2018.042 2018 12 25 2018 11 18 Background. The present study aimed to compare the amount of apically extruded debris and irrigants produced by various nickel-titanium instruments. Methods. A total of 100 single-rooted mandibular premolar teeth were root canal treated and prepared for agar gel model. The root canal fillings were removed using Reciproc Blue, ProTaper Next, R-Endo, WaveOne Gold systems or hand instrumentation. The mean weights of apically extruded materials were calculated. Data were statistically analyzed using one-way ANOVA and post hoc Bonferroni tests. Results. Hand instrumentation resulted in significantly more debris and irrigants than other systems (P<0.05). The mean amount of apically extruded debris and irrigants produced by Reciproc Blue system was significantly greater than motordriven instruments (P<0.05). No significant difference was detected between ProTaper Next and WaveOne Gold systems (P>0.05), while they both produced significantly less apically extruded material than R-Endo system (P<0.05). Conclusion. All the instruments caused apical extrusion. ProTaper Next and WaveOne Gold systems were associated with significantly less apical extrusion.