title: Evaluation of Apically Extruded Debris from Curved Root Canal Filling Removal Using 5 Nickel-Titanium Systems.
abstract: BACKGROUND
  This study evaluated the amount of apically extruded debris in the retreatment of curved root canals using different nickel-titanium (NiTi) systems: the ProTaper Universal Retreatment (Dentsply Maillefer, Ballaigues, Switzerland), Mtwo Retreatment (VDW, Munich, Germany), D-Race Retreatment (FKG Dentaire, La Chaux-de-Fonds, Switzerland), R-Endo Retreatment (Micro-Mega, Besançon, France), and Reciproc (VDW) systems.
  
  
  METHODS
  One hundred human mandibular premolars with curved root canals were prepared with the Reciproc #25 .08 NiTi system filled with AH Plus Jet (Dentsply DeTrey, Konstanz, Germany) sealer and gutta-percha and divided into 5 groups (n = 20). The canal filling was removed with the ProTaper, Mtwo, D-Race, and R-Endo retreatment systems and Reciproc instruments. Final preparation was done with the Reciproc #40 .06 NiTi system. Extruded debris was collected in preweighed Eppendorf tubes. The times required for retreatment were recorded.
  
  
  RESULTS
  Reciproc produced significantly (P < .001) more debris than the other systems. ProTaper R and Mtwo R produced significantly (P < .001) more debris than D-Race and R-Endo. The Reciproc group required significantly (P < .001) less preparation time than the other groups.
  
  
  CONCLUSIONS
  In the retreatment of curved root canals, the Reciproc system extruded significantly more debris than the rotary retreatment NiTi systems. In addition, the ProTaper and Mtwo retreatment systems extruded significantly more debris than the R-Endo and D-Race systems. The Reciproc system was significantly faster than the rotary retreatment systems.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Trakya University, Edirne, Turkey. Electronic address: burhancanakci@trakya.edu.tr.
authors.forename: Burhan Can
authors.initials: BC
authors.lastname: Çanakçi
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Erciyes University, Kayseri, Turkey.
authors.forename: Yakup
authors.initials: Y
authors.lastname: Ustun
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Trakya University, Edirne, Turkey.
authors.forename: Ozgur
authors.initials: O
authors.lastname: Er
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Yuzuncu Yil University, Van, Turkey.
authors.forename: Ozgur
authors.initials: O
authors.lastname: Genc Sen
mesh_terms: D001641:Bicuspid / Q000601:surgery; D003762:Dental Instruments; D003786:Dental Pulp Cavity; D004867:Equipment Design; D006171:Gutta-Percha; D006801:Humans; D066298:In Vitro Techniques; D008422:Materials Testing; D009532:Nickel; D012387:Root Canal Filling Materials; D012389:Root Canal Obturation / Q000295:instrumentation*; D014025:Titanium
chemical_list: D012387:Root Canal Filling Materials; C040654:titanium nickelide; D009532:Nickel; D006171:Gutta-Percha; D014025:Titanium
keywords: Apical extrusion; NiTi; debris extrusion; endodontic retreatment