title: Micro-Computed Tomographic Evaluation of 2 Nickel-Titanium Instrument Systems in Shaping Root Canals.
abstract: BACKGROUND
  Cleaning and shaping without making procedural errors have always been a challenge in endodontics, particularly when the root canals are curved. Several rotary instruments have been developed to minimize such errors. The purpose of this study was to compare the shaping ability of 2 rotary file systems, BioRace (BR; FKG, La Chaux-de-Fonds, Switzerland) and ProTaper Next (PTN; Dentsply Maillefer, Ballaigues, Switzerland), during the preparation of curved root canals in extracted teeth using micro-computed tomographic imaging.
  
  
  METHODS
  A total of 20 first and second human mandibular molars with 2 separate mesial canals were scanned before and after root canal preparations using the SkyScan 1176 X-ray microtomograph (Bruker microCT, Kontich, Belgium) at a resolution of 17.42 μm. Canals were prepared using the BR and PTN systems. The percentage of dentin removed after preparation, root canal volume increase, untreated canal walls, structure model index, degree of canal transportation, and centering ability were also measured.
  
  
  RESULTS
  There were no significant differences between the 2 groups in the removed dentin after preparation and determination of the root canal volume, percentage of untreated canal walls, structure model index, degree of canal transportation, and centering ability (P > .05).
  
  
  CONCLUSIONS
  In conclusion, within the limitations of this ex vivo study, instrumentation of moderately curved mesial roots with 2 independent root canals and foramina using the BR and PTN rotary file systems were equally effective. Both instrumentation systems caused negligible procedural errors with minimal apical transportation.
authors.affiliation: Department of Endodontics, Dental Reasearch Center, São Leopoldo Mandic University, Campinas, São Paulo, Brazil. Electronic address: grasielalimoeiro@gmail.com.
authors.forename: Ana Grasiela
authors.initials: AG
authors.lastname: da Silva Limoeiro
authors.affiliation: Department of Endodontics, School of Dentistry, Ilhéus University, Ilhéus, Bahia, Brazil.
authors.forename: Antônio Henrique Braitt
authors.initials: AH
authors.lastname: Dos Santos
authors.affiliation: Department of Endodontics, Dental Reasearch Center, São Leopoldo Mandic University, Campinas, São Paulo, Brazil.
authors.forename: Alexandre Sigrist
authors.initials: AS
authors.lastname: De Martin
authors.affiliation: Department of Endodontics, Dental Reasearch Center, São Leopoldo Mandic University, Campinas, São Paulo, Brazil.
authors.forename: Augusto Shoji
authors.initials: AS
authors.lastname: Kato
authors.affiliation: Department of Endodontics, Dental Reasearch Center, São Leopoldo Mandic University, Campinas, São Paulo, Brazil.
authors.forename: Carlos Eduardo
authors.initials: CE
authors.lastname: Fontana
authors.affiliation: Discipline of Endodontics, Department of Restorative Dentistry, School of Dentistry, University of São Paulo, São Paulo, São Paulo, Brazil.
authors.forename: Giulio
authors.initials: G
authors.lastname: Gavini
authors.affiliation: Discipline of Endodontics, Department of Restorative Dentistry, School of Dentistry, University of São Paulo, São Paulo, São Paulo, Brazil.
authors.forename: Laila Gonzales
authors.initials: LG
authors.lastname: Freire
authors.affiliation: Department of Endodontics, Dental Reasearch Center, São Leopoldo Mandic University, Campinas, São Paulo, Brazil.
authors.forename: Carlos Eduardo
authors.initials: CE
authors.lastname: da Silveira Bueno
mesh_terms: D000497:Alloys / Q000737:chemistry*; D003722:Dental Alloys / Q000737:chemistry*; D003786:Dental Pulp Cavity / Q000033:anatomy & histology; D003804:Dentin / Q000033:anatomy & histology; D004867:Equipment Design; D006801:Humans; D018915:Root Canal Preparation / Q000295:instrumentation*; D012390:Root Canal Therapy / Q000295:instrumentation* / Q000379:methods; D014092:Tooth Root; D055114:X-Ray Microtomography / Q000379:methods*
chemical_list: D000497:Alloys; D003722:Dental Alloys; C013616:nitinol
keywords: Apical transportation; BioRace; M-Wire; ProTaper Next; micro–computed tomographic imaging; nickel-titanium instrument