Abstract
This study compared step-back preparations in curved canals using nickel-titanium (Ni-Ti) K-files and stainless steel K-files. Forty canals in mesial roots of mandibular molars were embedded in casting resin and cross-sectioned at three levels: 1 to 2 mm from the apical foramen, middle of the curve, and coronal. Direct digital computer images were recorded before and after instrumentation. Superimposition of the images combined with digital subtraction computer software allowed direct measurement of area instrumented, distance of transportation, and shape analysis. The computer software calculated absolute center of gravity for each image analyzed to get a full 360-degree interpretation of the canal transport. Time of instrumentation was recorded. Results showed Ni-Ti files to cause significantly less transportation and remain more centered at the apical level (p < 0.05). Area removed by Ni-Ti and stainless steel files was not significantly different (p < 0.05). Time of instrumentation was not significantly different for Ni-Ti and stainless steel instruments (p < 0.05). Cross-sectional shape of the instrumented canal was not significantly different (p < 0.05).
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
