Mandibular Premolar Root Canal Cleaning Efficacy of Ultrasonic and Hand Debridement – A Scanning Electron Microscope Study

To evaluate and compare the cleaning efficacy of ultrasonic and hand debridement of mandibular premolar root canal using scanning electron microscope. A sample of thirty freshly extracted human mandibular premolar teeth with straight canal was employed in this study. Fifteen teeth were utilized for debridement with hand K files and 2.5 % sodium hypochlorite irrigation in group A. Similar number of specimens was used for ultrasonic debridement with endosonic K files and 2.5% sodium hypochlorite irrigation in group B. The roots were sectioned longitudinally and exposed to scanning electron microscope at cervical, middle and apical third level of the canal. The photomicrographs, obtained, were qualitatively and quantitatively evaluated by three endodontists. The qualitative and quantitative data was statistically analyzed by SND and unpaired t test respectively.It is revealed that grade I (clean) specimens are obtained only by ultrasonic debridement and Grade V (with severe débris) specimens are obtained only by hand debridement. Higher proportion of grade II photomicrographs is obtained in ultrasonic than hand debridement. Grade III and Grade IV are obtained in higher proportion by hand as compared to ultrasonic debridement. In quantitative analysis, it is seen that ultrasonically dehrided specimens are significantly cleaner than the hand debrided specimens (P < 0.01).