COMPARISON OF 2 STAINLESS-STEEL FILES TO SHAPE SIMULATED ROOT CANALS

The aim of this study was to compare the shaping ability of two stainl ess steel files using simulated canals, A total of 80 simulated canals of various angles and positions of curvature were prepared by hand us ing either Mani K-Files or Micro Mega K-Files, Following orifice enlar gement each file type was used to prepare 40 canals employing a linear filing motion and an anticurvature stepback technique, Pre- and post- operative longitudinal images of the canals were taken with a video ca mera and stored and manipulated in a computer with image analysis soft ware, The presence of canal aberrations and the amount of material rem oved as a result of preparation were determined from composite images of superimposed pre- and post-operative views, Overall, canal preparat ion with Mani K-Files was significantly quicker (P<0.005) and was asso ciated with fewer instrument failures, Zips and elbows were observed i n 70% of specimens with significantly more (P<0,05) occurring followin g preparation with Micro Mega K-Files, Mani K-Files created significan tly more (P<0.01) danger zones, Micro Mega K-Files created significant ly wider (P<0,001) zips with significantly more (P<0,01) resin removed from the outer aspect of the curves and, thus, significantly more (P< 0.01) transportation, Canal shape had a significant influence on prepa ration time (P<0,001), the incidence of zips (P<0,05) and danger zones (P<0,005), the width of zips (P<0,001) and transportation at the zips (P<0,001), Under the conditions of this study, Mani K-Files were more effective than Micro Mega K-Files and produced canals with better sha pes, Original canal shape had a substantial influence on the outcome o f shaping procedures.