The importance of irrigation is recently stressed upon with the advent of the new mechanized instrumentation technique that always recommended working in wet canals. The effectiveness of irrigation relies on both the mechanical flushing action and the chemical ability of irrigants to dissolve tissues.Both new devices, F-file and EndoActivator were compared to ultrasonic and traditional needle using different irrigant solutions (2.6% NaOCl, 17%EDTA, 2% CHX and 10% citric acid) in order to evaluate the effectiveness of each device to improve the cleaning capacity of these solutions. 160 single canalled mature teeth were instrumented using flexible K-files in a circumferential filing motion to ISO size # 50 and irrigated with 2ml of 2.6% NaOCl after each file. The samples were divided into four main groups according to the method used to activate the flushing solutions inside the canal. Each of the four main groups was subdivided into four subgroups according to the flushing agent that concluded the preparation. The1st subgroup A: (A1) NaOCl + Syringe, (A2) EDTA + Syringe, (A3) CHX + Syringe, (A4) citric acid + Syringe; The 2nd subgroup B: (B1) NaOCl + F-file, (B2) EDTA + F-file, (B3) CHX + F-file, (B4) citric acid + F-file: the 3rd subgroup C: (C1) NaOCl + EndoActivator, (C2) EDTA + EndoActivator, (C3) CHX + EndoActivator, (C4) citric acid + EndoActivator. The 4th subgroup D: (D1) NaOCl + Ultrasonic, (D2) EDTA + Ultrasonic, (D3) CHX + Ultrasonic, (D4) citric acid + Ultrasonic. The samples were finally flushed with 5ml of distilled water. The specimens were then longitudinally chiseled into two halves and examined under the stereomicroscope for gross debris. Three specimens from each group were further studied under the SEM for surface details for smear layer and open dentinal tubules. Stereomicroscopic results showed that none of the energized methods significantly improved the cleaning efficacy of NaOCl and CHX at any of the 3 root canal levels, when compared to the traditional use of the syringe. The syringe showed superior results with EDTA at coronal and middle levels when compared to the energized methods. However at the apical levels none of the devices significantly improved the cleaning efficacy of EDTA. Again syringe showed superior results with citric acid at all levels of the root canal while ultrasonic showed the inferior results. SEM results showed none of the used devices significantly affected the smear layer removal ability of the tested solutions.