Aim & Objectives: The aim of this study was to evaluate the effects, at 24 h and 8 days, of 5% NaOCl and 17% EDTA on the Vicker’s microhardness of Mineral Trioxide Aggregate(MTA Angelus) (MTAA), Biodentine(Septodont, Saint Maur des Fosse’s France) and Pozzolan based endodontic cement named Endocem MTA(Maruchi, Wonju, Korea). Materials and method: Sixty samples of MTAA, Biodentine and Endocem MTA were tested for baseline microhardness at 24 h. They were divided into 12 subgroups (5% NaOCl or 17% EDTA, 24 h and 5% NaOCl or 17% EDTA at 8 days) and microhardness was evaluated at different time points. Results were recorded and analysed statistically via one-way ANOVA and Tukey’s post hoc  test. Results: MTAA had a higher baseline microhardness than both biodentine and Endocem MTA. At 24 hrs, the microhardness of all the materials was reduced by NaOCl and EDTA. At 8 days, NaOCl reduced the microhardness of MTA but that of Biodentine and Endocem MTA was increased. EDTA at 8 days, reduced the microhardness of both MTAA and Biodentine but an increase was seen with Endocem MTA. Conclusion: Changes in microhardness of MTAA, Biodentine and Pozzolan cement(Endocem MTA) were associated with the time for which the materials are allowed to set as well as the irrigating agent used,.

BACKGROUND Extrusion of debris, bacteria, and irrigant effect the inter-appointment flare ups and post-operative outcome of the endodontic treatment. So, it is necessary to make every effort to minimize such extrusion during cleaning and shaping of the canals. The present study was done to compare and evaluate debris and irrigant extrusion from curved root canals using different Ni-Ti systems. METHODS 30 mesial roots of mandibular molars were used in this study. Crown were decoronated, working length and initial apical diameter was established. 1.5 % agar gel model was used in this study. Samples were assigned randomly into 3 groups (n = 10 teeth per group). ProTaper Next, One Shape, FANTA AF BLUE F ONE files were used according to the manufacturer’s instructions for canal instrumentation. Apically extruded debris and irrigant was computed after the biomechanical preparation and their comparative analysis for each of the instruments and experimental models was performed. RESULTS Statistically significant difference was found between the three experimental groups. (P < .05). CONCLUSIONS All the instruments produced apically extruded debris and irrigant, but least was seen with FANTA AF BLUE F ONE and maximum with One Shape among the experimental groups. KEY WORDS Apical Debris, Irrigant, NiTi Files