title: A comparison of Profile, Hero 642, and K3 instrumentation systems in teeth using digital imaging analysis.
abstract: OBJECTIVE
  To evaluate the changes in cross-sectional area morphology of curved canals after instrumentation with Profile((R)), Hero 642((R)), and K3((R)) using digital imaging analysis. Study design Thirty mesial mandibular curved canals were used (25-40 degrees ). The molars were embedded in resin and the roots were sectioned transversely at three levels: apical, middle, and coronal. The canals were randomly distributed into 3 groups for instrumentation using Profile.04 and.06, Hero 642, and K3. The pre- and postinstrumentation sections were digitized and areas corresponding to the canals were measured with image-processing software.
  
  
  RESULTS
  Hero eliminated significantly more dentine than K3 and Profile in all 3 sections (P <.01, ANOVA test), with no differences observed between the latter 2 systems (P >.05, Student-Newman-Keuls test). All 3 systems yielded a rounded canal morphology in the coronal, middle, and apical thirds.
  
  
  CONCLUSIONS
  Hero rotary instruments produced more changes in cross-sectional area of the root canal.
authors.affiliation: Department of Dental Pathology and Therapeutics, School of Dentistry, University of Granada, Spain. mpaloma@ugr.es
authors.forename: María Paloma
authors.initials: MP
authors.lastname: González-Rodrguez
authors.forename: Carmen María
authors.initials: CM
authors.lastname: Ferrer-Luque
mesh_terms: D000704:Analysis of Variance; D019412:Anatomy, Cross-Sectional; D003786:Dental Pulp Cavity / Q000473:pathology*; D003804:Dentin / Q000473:pathology; D004867:Equipment Design; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008963:Molar; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods; D019227:Tooth Apex / Q000473:pathology