title: Cone-Beam Computed Tomography Comparison of Canal Transportation after Preparation with BioRaCe and Mtwo Rotary Instruments and Hand K-Flexofiles.
abstract: BACKGROUND
  The aim of this in vitro study was to evaluate the transportation of mesiobuccal canals of mandibular first molars prepared with either BioRaCe or Mtwo rotary instruments or hand K-Flexofile, by means of cone-beam computed tomography (CBCT).
  
  
  METHODS
  Forty-five mandibular molars were selected and randomly divided into three groups (n=15). Mesiobuccal roots of these teeth were prepared by BioRaCe, Mtwo, or hand K-Flexofile. Transportation was measured by pre- and post-operative CBCT images. Two-way ANOVA analysis was applied to detect any differences between the groups followed by the post hoc Tukey's tests. The level of significance was set at 0.05.
  
  
  RESULTS
  The non-parametric Friedman test was used to compare the behavior of each file at 3-, 6- and 9-mm levels. There were no significant differences between different levels in Mtwo group (P=0.15); however, the differences in K-Flexofile and BioRaCe groups were significant (P>0.05). The post hoc Tukey's test revealed significant differences between BioRaCe and K-Flexofile and also between Mtwo and K-Flexofile, both in the 3-mm depths (P<0.05).
  
  
  CONCLUSIONS
  Under the limitations of the present study, BioRaCe and Mtwo rotary instruments are considered suitable for canal preparation to greater apical sizes provided that the recommended sequences are observed.
authors.affiliation: Dental and Periodontal Research Center, Department of Endodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Hadi
authors.initials: H
authors.lastname: Mokhtari
authors.affiliation: Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Niknami
authors.affiliation: Dental and Periodontal Research Center, Department of Orthodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Aydin
authors.initials: A
authors.lastname: Sohrabi
authors.affiliation: Dental and Periodontal Research Center, Department of Endodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Ehsan
authors.initials: E
authors.lastname: Habibivand
authors.affiliation: Dental and Periodontal Research Center, Department of Endodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Hamid Reza
authors.initials: HR
authors.lastname: Mokhtari Zonouzi
authors.affiliation: Dental and Periodontal Research Center, Department of Endodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Saeed
authors.initials: S
authors.lastname: Rahimi
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Vahid
authors.initials: V
authors.lastname: Zand
keywords: BioRaCe; CBCT; Canal Transportation; Cone-Beam Computed Tomography; Mtwo; Root Canal Preparation