 method. A total of 6 ml of 5.25% NaOCl was used, and the total activation time was 1 min.

Group 3: EndoActivator (EA) {#sec2-7}
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In this group, 3 ml of 5.25% NaOCl was flushed into the canal and activated with the red EndoActivator (25.04) tip at 10,000 cycles/min. The tip was placed inside the canal at 1 mm short of the WL and operated using an up-and-down motion for 30 s. The canals were then flushed with 3 ml of 5.25% NaOCl and activated using the same method for 30 s. A total of 6 m of 5.25% NaOCl was used, and the total activation time was 1 min.

Group 4: IrriSafe (IS) {#sec2-8}
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The additional irrigation was activated using an ultrasonic tip; 3 ml of 5.25% NaOCl was flushed into the canal and ultrasonically agitated with the IrriSafe tip \#25/25 which was placed inside the canal mm short of the WL and operated using an up-and-down motion for 30 s. The canals were then flushed with 3 ml of 5.25% NaOCl and activated using the same method for 30 s. The ultrasonic tip was placed into the canal 1 mm short of the WL, without touching the walls, enabling it to vibrate freely. A total of 6 ml of 5.25% NaOCl was used, and the total activation time was 1 min.

Evaluation of residual Gutta-percha and sealer {#sec2-9}
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The teeth were grooved buccolingually using a stainless steel disc and then split into halves using a chisel and mallet. Digital images at 8× magnification were obtained from both halves under a stereomicroscope (Olympus BX43, Olympus Co., Tokyo, Japan) attached to a digital camera. The photographs were analysed using AutoCAD (Autodesk, San Rafael, CA, USA) software to measure the areas of residual gutta-percha and sealer ([Figure 2](#F2){ref-type="fig"}).

![a-d. Measurement of residual gutta-percha and sealer via AutoCAD software (a) Conventional Irrigation (b) XP-endo Finisher (c) IrriSafe (d) EndoActivator](EEJ-1-6-g002){#F2}

Statistical analysis {#sec2-10}
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According to the Kol