title: Influence of Cervical and Apical Enlargement Associated with the WaveOne System on the Transportation and Centralization of Endodontic Preparations.
abstract: BACKGROUND
  The aim of this study was to evaluate through computed microtomography the transportation and centralization of root canals instrumented using the WaveOne system (Dentsply Maillefer, Ballaigues, Switzerland) associated or unassociated with previous apical and cervical enlargements.
  
  
  METHODS
  Thirty-six mandibular molars were selected with independent mesial roots and curvatures and randomized into the following groups: PathFile (Dentsply Maillefer) before WaveOne Primary (the PFWO group), ProTaper Universal SX (Dentsply Maillefer) before WaveOne Primary (the SXWO group), and WaveOne Primary (the WO group). Computed microtomographic imaging was performed pre- and postpreparation to obtain measurements of mesial and distal dentin walls and calculations of root canal transportation (%) and centralization. One-way analysis of variance was performed to compare the different groups, repeated measures analysis of variance for comparison of the root thirds in each group, and the Student t test for comparisons between the mesiobuccal and mesiolingual canals.
  
  
  RESULTS
  Transportation of the cervical and middle thirds to the danger zone was observed in both roots, whereas the apical thirds were transported to the outer face of the curvature. In the PFWO and SXWO groups, less transportation was observed in the middle thirds of the mesiobuccal canals compared with the WO group (P < .05). Centralization remained almost unchanged in the SXWO group (P < .05).
  
  
  CONCLUSIONS
  In each group, transportation toward the danger zone was mostly observed in the cervical thirds of the mesiobuccal canals. Cervical or apical enlargement resulted in reduced transportation and improved centralization of the middle thirds compared with the exclusive use of the WaveOne system.
authors.affiliation: Department of Dentistry, Positivo University, Curitiba, Paraná, Brazil.
authors.forename: Rodrigo Otavio
authors.initials: RO
authors.lastname: Jatahy Ferreira do Amaral
authors.affiliation: Department of Dentistry, Positivo University, Curitiba, Paraná, Brazil.
authors.forename: Denise Piotto
authors.initials: DP
authors.lastname: Leonardi
authors.affiliation: Department of Dentistry, Positivo University, Curitiba, Paraná, Brazil. Electronic address: marilisagabardo@e-odonto.com.
authors.forename: Marilisa Carneiro Leão
authors.initials: MC
authors.lastname: Gabardo
authors.affiliation: Department of Dentistry, Positivo University, Curitiba, Paraná, Brazil.
authors.forename: Beatriz Serrato
authors.initials: BS
authors.lastname: Coelho
authors.affiliation: Department of Dentistry, Positivo University, Curitiba, Paraná, Brazil.
authors.forename: Kauhanna Vianna de
authors.initials: KV
authors.lastname: Oliveira
authors.affiliation: Department of Dentistry, Positivo University, Curitiba, Paraná, Brazil.
authors.forename: Flares
authors.initials: F
authors.lastname: Baratto Filho
mesh_terms: D003722:Dental Alloys / Q000737:chemistry; D003762:Dental Instruments; D003786:Dental Pulp Cavity / Q000033:anatomy & histology*; D004867:Equipment Design / Q000295:instrumentation*; D006801:Humans; D008963:Molar / Q000033:anatomy & histology; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods; D012390:Root Canal Therapy / Q000295:instrumentation* / Q000379:methods; D019227:Tooth Apex / Q000033:anatomy & histology; D014092:Tooth Root / Q000033:anatomy & histology
chemical_list: D003722:Dental Alloys
keywords: Canal transportation; WaveOne; centralization; endodontics