Minimal invasive dentistry and endodontic technological revolution used in endodontic treatment enable the application of conservative endodontic access(CEC)cavity to minimize tooth structure removal.This study examined the cleanliness of CEC.Methods:Eighty sound extracted upper first premolar divided into 4groups (n=20)according to the irrigation protocol G1:Conventional method with Irriflex irrigating needle;G2: ENDOVAC negative pressure irrigation system;G3: PUI with ED62 irrigation ultrasonic tip;G4: Er,Cr:YSGG Laser SWEEPS Mode. CEC done under high magnification.After instrumentation with M3ProGold rotary file to size 35/0.04 taper and irriganted, specimens examined under SEM, and cleanliness of pulp chamber and root canal walls at coronal,middle,apical third was measured. Data were measured, tabulated and statistically analyzed by ANOVA and t-student test (P