An in vitro comparison of hand and rotary instruments in preparing root canal system.

The aims of the present study are to compare hand stainless steel K-files and Nickel titanium Profile 0.04 taper 29 series rotary instruments for their efficiency, procedure errors and time consumed in preparation of root canal system. About 46 freshly bilaterally extracted first premolars were selected. They were divided into two groups, each group with sum of 34 canals. First group teeth were prepared with k-files while the second group was prepared with profile 0.4 taper series 29 rotary files. Preparation time was recorded for both groups. Impression material were introduced to the lumen of the prepared canals and the three dimensional shape of the prepared canals were assessed under magnification of stereomicroscope to assess the efficiency in preparing canals including canal smoothness, flow and taper. showed significantly shorter preparation time for Profile than K-file. 8.8% of the canals prepared with hand K-file showed canal blockage. Change in working distance appeared in 23.5% of canals prepared with K-file and 11.7% in canals prepared with Profile. Failed instruments were significantly higher in K-files; in the form of deformation. Profiles failed instruments were in the form of fracture and no deformation detected. Both systems showed unsatisfactory walls smoothness and flow. Good taper were highly significant in K-files preparations. suggesting the use of a technique that combines the two systems in canals preparation to overcome problems associated with each system