title: A comparison of the shaping abilities of 4 nickel-titanium rotary instruments in simulated root canals.
abstract: OBJECTIVE
  The purpose of this study was to compare the root canal shaping abilities of 4 nickel-titanium rotary instruments.
  
  
  METHODS
  ProFile, GT Rotary, Quantec, and ProTaper files were used to instrument 48 simulated curved root canals in plastic blocks with the crown-down technique. One operator prepared all the canals until reaching an apical canal size of #30. The instrumentation time, changes of canal dimension and curvature, canal aberration, and instrument deformation were evaluated. Data were analyzed by using one-way analysis of variance followed by the Duncan multiple range test.
  
  
  RESULTS
  The ProTaper took significantly less instrumentation time, removed more canal wall (especially at the inner side of the canal curve), lessened the canal curvature, and induced more instrument deformation than did the other instruments.
  
  
  CONCLUSIONS
  Although ProTaper files cut more canal wall more quickly than the other instruments in the curved canal, they were also the instruments that most frequently became deformed.
authors.affiliation: Department of Conservative Dentristry, School of Dentistry, Kyungpook National University, Daegu, Korea.
authors.forename: Hyung-Hwa
authors.initials: HH
authors.lastname: Yun
authors.forename: Sung Kyo
authors.initials: SK
authors.lastname: Kim
mesh_terms: D000704:Analysis of Variance; D003762:Dental Instruments; D003786:Dental Pulp Cavity / Q000033:anatomy & histology; D004867:Equipment Design; D004868:Equipment Failure; D006801:Humans; D009532:Nickel; D009811:Odontometry; D018915:Root Canal Preparation / Q000295:instrumentation*; D018709:Statistics, Nonparametric; D013997:Time Factors; D014025:Titanium
chemical_list: C040654:titanium nickelide; D009532:Nickel; D014025:Titanium