title: Comparison of the effects of TripleGates and Gates-Glidden burs on cervical dentin thickness and root canal area by using cone beam computed tomography.
abstract: The search for new instruments to promote an appropriate cervical preparation has led to the development of new rotary instruments such as TripleGates. However, to the best of the authors' knowledge, there is no study evaluating TripleGates effect on the "risk zone" of mandibular molars.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the effects of a crown-down sequence of Gates-Glidden and TripleGates burs on the remaining cervical dentin thickness and the total amount of dentin removed from the root canals during the instrumentation by using cone beam computed tomography. The number of separated instruments was also evaluated.
  
  
  METHODS
  Mesial roots of 40 mandibular first molars were divided into 2 equal groups: crown-down sequence of Gates-Glidden (#3, #2, #1) and TripleGates burs. Cervical dentin thickness and canal area were measured before and after instrumentation by using cone beam computed tomography and image analysis software. Student's t-test was used to determine significant differences at p < 0.05.
  
  
  RESULTS
  No significant differences (p > 0.05) were observed between the instruments, regarding the root canal area and dentin wall thickness.
  
  
  CONCLUSIONS
  Both tested instruments used for cervical preparation were safe to be used in the mesial root canal of mandibular molars.
authors.affiliation: Private Practice, Jequié, BA, Brazil.
authors.forename: Kássio
authors.initials: K
authors.lastname: Sousa
authors.affiliation: Estácio de Sá University, Rio de Janeiro, RJ, Brazil.
authors.forename: Carlos Vieira
authors.initials: CV
authors.lastname: Andrade-Junior
authors.affiliation: Federal University of Pará, Belém, PA, Brazil.
authors.forename: Juliana Melo da
authors.initials: JM
authors.lastname: Silva
authors.affiliation: Departament of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
authors.forename: Marco Antonio Hungaro
authors.initials: MA
authors.lastname: Duarte
authors.affiliation: Health Sciences Center, Grande Rio University, Rio de Janeiro, RJ, Brazil.
authors.forename: Gustavo
authors.initials: G
authors.lastname: De-Deus
authors.affiliation: Health Sciences Center, Grande Rio University, Rio de Janeiro, RJ, Brazil.
authors.forename: Emmanuel João Nogueira Leal da
authors.initials: EJ
authors.lastname: Silva
mesh_terms: D054893:Cone-Beam Computed Tomography / Q000379:methods*; D003762:Dental Instruments; D003786:Dental Pulp Cavity / Q000000981:diagnostic imaging*; D003804:Dentin / Q000000981:diagnostic imaging*; D004867:Equipment Design; D006801:Humans; D021621:Imaging, Three-Dimensional; D008855:Microscopy, Electron, Scanning; D008963:Molar; D015203:Reproducibility of Results; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods