title: Cyclic fatigue resistance of different continuous rotation and reciprocating endodontic systems.
abstract: OBJECTIVE
  The objective of this study is to compare the cyclic fatigue resistance of nine types of endodontic instruments of nickel-titanium.
  
  
  METHODS
  Five files of 25 mm of length of each group: Reciproc (RC) R25; WaveOne (WO) Primary; Unicone (UC) L25 25/0.06; K3XF 25/0.06; ProTaper Universal F2 (PTF2); ProTaper Next X2 (PTX2); Mtwo 25/0.06; BioRaCe 25/0.06; One Shape L25 25/0.06 were subjected to a cyclic fatigue resistance test on a mechanical apparatus. The mean fracture time was analyzed statistically by one-way analysis of variance and Tukey's honest significant difference post hoc test, with significance set at P< 0.05.
  
  
  CONCLUSIONS
  It was observed that the groups PTX2, RC, R25, UC L25 25/0.06, and WO Primary presented greater cyclic fracture resistance than the other groups (P< 0.001).
authors.affiliation: Department of Endodontic, University of Fortaleza (UNIFOR), Fortaleza, Ceará, Brazil.
authors.forename: Fabio
authors.initials: F
authors.lastname: de Almeida-Gomes
authors.affiliation: Department of Restorative Dentistry and Endodontic, Piracicaba Dental School (UNICAMP), Piracicaba, São Paulo, Brazil.
authors.forename: Humberto Ramah Menezes
authors.initials: HR
authors.lastname: de Matos
authors.affiliation: Department of Endodontic, University of Fortaleza (UNIFOR), Fortaleza, Ceará, Brazil.
authors.forename: Rodrigo Ferreira Lopes Arrais
authors.initials: RF
authors.lastname: Nunes
authors.affiliation: Department of Endodontic, University of Fortaleza (UNIFOR), Fortaleza, Ceará, Brazil.
authors.forename: Ariel Moura
authors.initials: AM
authors.lastname: Arrais
authors.affiliation: Department of Endodontic, University of Fortaleza (UNIFOR), Fortaleza, Ceará, Brazil.
authors.forename: Claudio
authors.initials: C
authors.lastname: Ferreira-Maniglia
authors.affiliation: Department of Endodontic, University of Fortaleza (UNIFOR), Fortaleza, Ceará, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: de Morais Vitoriano
authors.affiliation: Department of Endodontic, University of Fortaleza (UNIFOR), Fortaleza, Ceará, Brazil.
authors.forename: Eduardo Diogo
authors.initials: ED
authors.lastname: Gurgel-Filho
mesh_terms: D003722:Dental Alloys; D003762:Dental Instruments; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008422:Materials Testing; D009532:Nickel; D018915:Root Canal Preparation / Q000295:instrumentation*; D012399:Rotation; D012984:Software; D013499:Surface Properties; D014025:Titanium
chemical_list: D003722:Dental Alloys; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium