title: A comparison of the shaping effects of 5 nickel-titanium rotary instruments in simulated S-shaped canals.
abstract: OBJECTIVE
  The objective of this study was to compare the shaping efficacy of 5 Ni-Ti rotary instruments with different cross-sectional designs in simulated S-shaped resin root canals.
  
  
  METHODS
  One hundred canals (n = 20) were instrumented to apical size 0.04/25 with ProFile, K3, NiTi-TEE, EndoWave, or HeroShaper. Pre- and postoperative images were superimposed. Width of resin removal was measured. Total amount of material removal, amount and direction of transportation, and centering ratios were determined. Data were analyzed using 1-way ANOVA and post hoc Tukey and Newman-Keuls multiple comparison tests.
  
  
  RESULTS
  In terms of centering ratio and amount of transportation, ProFile followed by K3 gave the best results almost throughout the whole canal. However, ProFile created insufficient taper. Canals instrumented with the other 3 systems were transported and lacked flow.
  
  
  CONCLUSIONS
  The K3 system, probably owing to its cross-sectional design and sequence encompassing a high number of instruments, seems under the conditions of this study to be a better choice in preparing S-shaped simulated root canals.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Istanbul University, Istanbul, Turkey. ersev@istanbul.edu.tr
authors.forename: Handan
authors.initials: H
authors.lastname: Ersev
authors.forename: Bülent
authors.initials: B
authors.lastname: Yilmaz
authors.forename: Elif
authors.initials: E
authors.lastname: Ciftçioğlu
authors.forename: Sükrü Fatih
authors.initials: SF
authors.lastname: Ozkarsli
mesh_terms: D003722:Dental Alloys / Q000737:chemistry*; D003786:Dental Pulp Cavity / Q000033:anatomy & histology*; D004867:Equipment Design; D006801:Humans; D008422:Materials Testing; D009532:Nickel / Q000737:chemistry*; D023861:Photography, Dental; D018915:Root Canal Preparation / Q000295:instrumentation*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D003722:Dental Alloys; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium