title: Comparison of nickel-titanium and stainless steel hand-file instrumentation using computed tomography.
abstract: Computed tomography was used to evaluate root canals prepared by nickel-titanium (Ni-Ti) hand and stainless steel hand endodontic instruments. Thirty-six single-rooted teeth of similar shape and canal size were divided into three groups. The teeth were scanned by computed tomography before instrumentation. In group A, canals were instrumented using a quarter turn/pull technique with K-flex files. In group B, canals were prepared with Ni-Ti hand files (Mity files) using the same technique as group A. Group C was prepared with Ni-Ti hand files (Mity files) using a reaming technique. Instrumented teeth were again scanned using computed tomography, and reformated images of the uninstrumented canals were compared with images of the instrumented canals. Ni-Ti instruments (Mity file) used in a reaming technique caused significantly less canal transportation (p < 0.05), removed significantly less volume of dentin (p < 0.05), required less instrumentation time (p < 0.05), and produced more centered and rounder canal preparations than K-flex stainless steel files used in a quarter turn/pull technique. The computed tomography imaging system used in this study provided a repeatable, noninvasive method of evaluating certain aspects of endodontic instrumentation.
authors.affiliation: Department of Endodontics, Wilford Hall U.S. Air Force Medical Center, Lackland Air Force Base, TX, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Gambill
authors.forename: M
authors.initials: M
authors.lastname: Alder
authors.forename: C E
authors.initials: CE
authors.lastname: del Rio
mesh_terms: D000704:Analysis of Variance; D003722:Dental Alloys; D003762:Dental Instruments; D003786:Dental Pulp Cavity / Q000000981:diagnostic imaging; D005069:Evaluation Studies as Topic; D006801:Humans; D009532:Nickel; D015588:Observer Variation; D015203:Reproducibility of Results; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods*; D013193:Stainless Steel; D013997:Time Factors; D014025:Titanium; D014057:Tomography, X-Ray Computed
chemical_list: D003722:Dental Alloys; C040654:titanium nickelide; D013193:Stainless Steel; D009532:Nickel; D014025:Titanium