Introduction: Many advantages of the self- ligating (SL) brackets over the conventional (CL) ones have been claimed. The aim of this study was to evaluate and compare the effect of SmartClip SL brackets and conventional brackets on affecting the rate of passive extraction space closure by the canines and the axial inclination and tip of the teeth in extraction cases, during the leveling and alignment stage. The chairside time and the speed of the leveling and alignment stage were estimated and compared. Material and Methods: 10 patients with severe crowding received the SmartClip bracket in both its original SL form and in a CL form (after modifying it) in a split mouth study. The wire sequence for leveling and alignment was 0.014’’, 0.016’’, 0.018’’ x 0.025’’ NiTi followed by 0.019’’ x 0.025’’ StSt archwires with each archwire left in place for 8weeks. Pre and post alignment CBCT images were taken for each patient and the tip, torque and vertical position of each tooth was measured. The ABO cast radiograph system was used to assess the pre, post and mid treatment casts as well. Results: The SL brackets showed a statistically significant less mean of duration of the leveling and alignment together with the chairside time. The CL brackets showed a statistically significant higher mean distal tipping of teeth than the SL brackets. There were no statistically significant differences among the two brackets in any of the other measured aspects whether on the cast or on the CBCT images. Conclusions: Passive SL brackets were not more efficient than the CL brackets in affecting the alignment of the crowded teeth during the leveling and alignment phase. They only showed a clinically modest less duration of alignment and chairside time compared to the CL brackets.