title: Comparison of three instruments in the preparation of curved root canals.
abstract: The transportation produced in the apical and middle areas of 30 mesiobuccal root canals of human mandibular molars was evaluated after circumferential instrumentation using stainless steel K-files (group A), nickel-titanium K-files (group B), and clockwise/counterclockwise file rotation using Flexogates (group C). The canals were instrumented with files #15 to #35 in size. Apical transportation was assessed radiographically while that occurring in the middle area was studied microscopically in cross-sections. Although apical transportation was greatest in the canals of group A, this difference was not statistically significant (P > 0.05). With respect to the middle area of the root canal, considerable transportation was observed in 7 of the 30 instrumented roots. Of these, five belonged to group A and two to group B, a difference which was not statistically significant (P > 0.05). The best results for transportation in the middle area of the canal were obtained in group C, in which no transportation occurred. This difference was significant when compared with the transportation observed in group A (P = 0.02) but not with that in group B (P > 0.05).
authors.affiliation: Department of Endodontics, School of Dentistry, University del Salvador-Asociación Odontológica Argentina, Buenos Aires.
authors.forename: F
authors.initials: F
authors.lastname: Goldberg
authors.forename: J A
authors.initials: JA
authors.lastname: Araujo
mesh_terms: D003722:Dental Alloys; D003786:Dental Pulp Cavity / Q000000981:diagnostic imaging; D005069:Evaluation Studies as Topic; D006801:Humans; D066298:In Vitro Techniques; D008334:Mandible; D008422:Materials Testing; D008963:Molar / Q000000981:diagnostic imaging; D009532:Nickel; D011859:Radiography; D011897:Random Allocation; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000592:standards; D013193:Stainless Steel; D014025:Titanium
chemical_list: D003722:Dental Alloys; C040654:titanium nickelide; D013193:Stainless Steel; D009532:Nickel; D014025:Titanium