مقايسه سه روش آماده سازي كانال بر ميزان جابجايي اپيكالي كانال هاي انحناءدار ريشه دندان با دو روش اندازه گيري

An in vitro comparison of three instrumentation techniques on apical transportation of curved root canals by two measurement methods

Aim: A basic tenet in endodontic therapy is the thorough cleaning and shaping of the root canal system, while maintaining the original canal configuration. It has been demonstrated that the files tend to straighten once introduced into the curved, resulting in excessive removal of dentin on the outside wall of the curvature which is called apical transportation (AT). The purpose of this study was to compare the amount of AT resulting from three instrumentation techniques. Method & Material: The study was done on 45 extracted human roots with 20-43° curvature. All roots were prepared by rotary (profile) and hand (balanced - force, step-back) techniques. The resulting AT was measured by double exposure radiographic projection method and by using computer analysis through photoshop 5.5 software. Results: There was no statistically significant difference of AT between three experimental groups (P<0.05) and no difference between two measurement methods (P<0.05). Conclusion: Under the condition of this study, it seems that step back to be as effective as profile and balanced- force in preparing curved root canals.