title: Incidence of dentinal cracks after root canal preparation with ProTaper Gold, Profile Vortex, F360, Reciproc and ProTaper Universal instruments.
abstract: OBJECTIVE
  To assess the effect of root canal preparation using ProTaper Gold, Profile Vortex, F360, Reciproc and ProTaper Universal instruments on dentinal crack formation.
  
  
  METHODS
  Ninety mandibular central incisor teeth with mature apices and straight canals (<5°) were selected and stored in distilled water. Fifteen teeth were left unprepared (control group) and the remaining 75 teeth were assigned to the five root canal shaping groups (n = 15): ProTaper Gold, ProFile Vortex, F360, Reciproc and ProTaper Universal. All the roots were sectioned perpendicular to the long axis at 3, 6 and 9 mm from the apex with a low-speed saw under water cooling. The slices were then viewed through a stereomicroscope at 25×  magnification. The presence of dentinal cracks was determined by photographing all samples using a digital camera.
  
  
  RESULTS
  All the experimental groups, except F360, produced significantly more cracks than the control group (P < 0.05). No significant difference was observed amongst the groups at the 6 and 9 mm levels (P > 0.05). The ProTaper Universal group produced significantly more cracks than the control, ProTaper Gold, ProFile Vortex, F360 and Reciproc groups at the apical section (3 mm) (P < 0.05).
  
  
  CONCLUSIONS
  All the systems that were tested produced dentinal cracks. There was no significant difference between the control and F360 groups in terms of dentinal crack formation.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Ataturk University, Erzurum, Turkey.
authors.forename: E
authors.identifier: http://orcid.org/0000-0002-8145-8763
authors.initials: E
authors.lastname: Karataş
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Ataturk University, Erzurum, Turkey.
authors.forename: H A
authors.initials: HA
authors.lastname: Gündüz
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Ataturk University, Erzurum, Turkey.
authors.forename: D Ö
authors.initials: DÖ
authors.lastname: Kırıcı
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Ataturk University, Erzurum, Turkey.
authors.forename: H
authors.initials: H
authors.lastname: Arslan
keywords: F360; ProFile Vortex; ProTaper Gold; Reciproc; crack