title: Influence of operator's experience on root canal shaping ability with a rotary nickel-titanium single-file reciprocating motion system.
abstract: BACKGROUND
  The aim of this study was to evaluate the influence of the operator's experience on the shaping of double-curvature simulated root canals with a nickel-titanium single-file reciprocating motion system.
  
  
  METHODS
  Sixty double-curvature root canals simulated in methacrylate blocks were prepared by 10 students without any experience in endodontics and by 10 professionals who had studied endodontics at the postgraduate level. The Reciproc-VDW system's R25 file was used in the root canal preparation. The blocks were photographed before and after the instrumentation, and the time of instrumentation was also evaluated. Changes in root canal dimensions were analyzed in 6 positions.
  
  
  RESULTS
  Significant differences (P < .05) were found in the apical transport of the first root canal curvature, with a larger percentage of increase of the root canal occurring in the novice group than in the expert one, as well as in the canal deviation at the beginning of the curvatures, whereas no significant results were obtained in the growth rate of the canal area. There was difference in the time of instrumentation, with 3.76 minutes observed in the novice group, as opposed to 2.05 minutes in the expert group.
  
  
  CONCLUSIONS
  The use of the single-file reciprocating motion system Reciproc is not seen to be influenced by the operator's experience regarding the increase of the canal area. Previous training and the need to acquire experience are important in the use of this system, in spite of its apparent simplicity.
authors.affiliation: Department of Stomatology, Universitat de València, Valencia, Spain.
authors.forename: Estefanía
authors.initials: E
authors.lastname: Muñoz
authors.affiliation: Department of Stomatology, Universitat de València, Valencia, Spain. Electronic address: forner@uv.es.
authors.forename: Leopoldo
authors.initials: L
authors.lastname: Forner
authors.affiliation: Department of Stomatology, Universitat de València, Valencia, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Llena
mesh_terms: D002983:Clinical Competence; D003722:Dental Alloys / Q000737:chemistry*; D003786:Dental Pulp Cavity / Q000033:anatomy & histology; D004708:Endodontics; D004867:Equipment Design; D006801:Humans; D008689:Methacrylates / Q000737:chemistry; D008953:Models, Anatomic; D009532:Nickel / Q000737:chemistry*; D010781:Photography / Q000379:methods; D018915:Root Canal Preparation / Q000295:instrumentation*; D012399:Rotation; D013335:Students, Dental; D013997:Time Factors; D014025:Titanium / Q000737:chemistry*
chemical_list: D003722:Dental Alloys; D008689:Methacrylates; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium
keywords: Dental education; endodontics; reciprocating motion; root canal shaping; simulated root canals