title: Comparison of apically extruded debris after root canal instrumentation using Reciproc(®) instruments with various kinematics.
abstract: OBJECTIVE
  To assess the amount of apically extruded debris using Reciproc(®) instruments with different kinematics (150° counter clockwise [CCW]-30° clockwise [CW], 270° CCW-30° CW, 360° CCW-30° CW and continuous rotation).
  
  
  METHODS
  Forty-eight maxillary central incisors were selected and assigned to four root canal shaping groups as follows (n = 12): 150° CCW-30° CW, 270° CCW-30° CW, 360° CCW-30° CW and continuous rotation. Reciproc R25 and R50(®) instruments were used in all groups. Apically extruded debris was collected and dried in preweighed Eppendorf tubes. The weight of extruded debris was assessed with an electronic balance. The data were analysed with one way analysis of variance and LSD post hoc tests (P = 0.05).
  
  
  RESULTS
  The 150° CCW-30° CW and 270° CCW-30° CW reciprocating motions extruded significantly less debris than continuous rotation (P < 0.05). However, no significant differences were found between the 360° CCW and 30° CW reciprocating motion and the continuous rotation (P > 0.05).
  
  
  CONCLUSIONS
  All instrument movements were associated with apically extruded debris. However, the 150° CCW-30° CW and 270° CCW-30° CW reciprocating motions were associated with less extrusion than continuous rotation.
authors: Department of Endodontics, Faculty of Dentistry, Ataturk University, Erzurum, Turkey.
authors: H
authors: H
authors: Arslan
authors: Department of Endodontics, Faculty of Dentistry, Ataturk University, Erzurum, Turkey.
authors: E
authors: E
authors: Doğanay
authors: Department of Endodontics, Faculty of Dentistry, Ataturk University, Erzurum, Turkey.
authors: M
authors: M
authors: Alsancak
authors: Department of Endodontics, Faculty of Dentistry, Izmir Katip Çelebi University, İzmir, Turkey.
authors: I D
authors: ID
authors: Çapar
authors: Department of Endodontics, Faculty of Dentistry, Ataturk University, Erzurum, Turkey.
authors: E
authors: http://orcid.org/0000-0002-8145-8763
authors: E
authors: Karataş
authors: Department of Endodontics, Faculty of Dentistry, Ataturk University, Erzurum, Turkey.
authors: H A
authors: HA
authors: Gündüz
mesh_terms: D001696:Biomechanical Phenomena; D003762:Dental Instruments; D004867:Equipment Design; D006801:Humans; D066298:In Vitro Techniques; D007180:Incisor / Q000601:surgery*; D008437:Maxilla; D018915:Root Canal Preparation / Q000295:instrumentation*
keywords: debris extrusion; kinematics; motion; movement; reciprocation; rotary