Objectives: The purpose of the study was to assess the amount of residual root canal filling materials (Guttapercha/Bioceramic sealer) after using different irrigation protocols.
Methodology: FortyMandibular premolar teeth were mechanically instrumented using Protaper Next rotary system and obturated with guttapercha master cones (size 25, 0.06 taper) coated with Sure Seal bioceramic sealer (Sure Dent Corp., Gyeonggi-do, Korea). All specimens were incubated for 4 weeks then retreatment was performed using Protaper Universal retreatment system. The specimens were randomly divided into four equal groups (n=10) according to the final irrigation protocol as follow; Conventional needle irrigation, Endovac, UltraX, Passive ultrasonic irrigation. Roots were grooved buccolingualy into two halves. A digital camera connected to the stereomicroscope captured images to each half. The root canals were segmented into thirds (Apical, middle and coronal). Image-J softwarewas used to evaluate and measure the areas with the remaining filling material in each third. Data were analysed using One-way ANOVA followed by Tukey's post hoc test for intergroup comparisons while One-way repeated measures ANOVA was used for intra group comparisons.
Results: All groups showed residual filling material in the root canals. The amount of the residual filling materials was significantly reduced upon using passive ultrasonic irrigation (P<0.001).
Conclusion: None of the irrigant activation methods was capable of completely removing the root canal filling material. Passive Ultrasonic irrigation enhanced the retreatment procedure of root canals previously obturated with gutta percha/bioceramic sealer.