title: Shaping ability of reciprocating single-file and full-sequence rotary instrumentation systems in simulated curved canals.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the shaping ability of three nickel-titanium systems in simulated curved canals.
  
  
  METHODS
  Sixty simulated canals were prepared to apical size 25 with Reciproc, S5, and twisted file (TF) instruments. Standardized pre and postoperative images were taken using a digital camera, were superimposed and aberrations were recorded. Material removal was measured at five points: The canal orifice, halfway to the orifice, beginning of the curve, the apex of the curve, and end-point. The data were analyzed using Kolmogorov-Smirnov, analysis of variance, and Tukey tests.
  
  
  RESULTS
  The mean total width of the prepared canals in the Reciproc group was greater than the TF and S5 groups at halfway to the orifice, the beginning of the curve, the apex of the curve, and the end-point (P < 0.05). Mean absolute transportation was always <0.16 mm; however, significant differences occurred between the three systems at the orifice, halfway to the orifice, and the beginning of the curve (P < 0.05). TF created minimal absolute transportation at halfway to the orifice and the beginning of the curve, and greater absolute transportation at the orifice compared with the Reciproc and S5 instruments. However, the difference between the S5 and TF groups was not statistically significant at halfway to the orifice (P > 0.05).
  
  
  CONCLUSIONS
  Under the conditions of the study, Reciproc produced widest canal shapes. TF provided more centered apical preparation and maintained the original canal shape well.
authors.affiliation: Department of Endodontics, Cumhuriyet University, Sivas, Turkiye.
authors.forename: Demet
authors.initials: D
authors.lastname: Altunbas
authors.affiliation: Department of Endodontics, Oral and Dental Health Center, Republic of Turkey Ministry of Health, Mersin, Turkiye.
authors.forename: Betul
authors.initials: B
authors.lastname: Kutuk
authors.affiliation: Department of Endodontics, Akdeniz University, Antalya, Turkiye.
authors.forename: Alper
authors.initials: A
authors.lastname: Kustarci
keywords: Canal transportation; Reciproc; S5; shaping; twisted file