title: Effectiveness of different irrigation systems on smear layer removal: A scanning electron microscopic study.
abstract: OBJECTIVE
  To evaluate effectiveness of the apical negative pressure irrigation (EndoVac), passive ultrasonic irrigation (PUI), and conventional needle irrigation (CI) systems on smear layer (SR) removal.
  
  
  METHODS
  Sixty single-rooted canines were prepared using NiTi rotary files and subjected to different irrigation regimens: EndoVac with NaOCl (Group 1) or NaOCl/EDTA (Group 2); PUI with NaOCl (Group 3) or NaOCl/EDTA (Group 4); CI with NaOCl (Group 5) or NaOCl/EDTA (Group 6). The roots were split longitudinally. SEM images were taken to evaluate the amount of residual SR.
  
  
  RESULTS
  In Groups 1, 3, and 5, there was no removal of SR (P > 0.05). The coronal thirds within Groups 2, 4, and 6 were cleaned completely, but the middle and the apical thirds was achieved partially or completely (P > 0.05).
  
  
  CONCLUSIONS
  Regardless of which irrigation system was used, the use of NaOCl alone failed to remove the SR. In NaOCl/EDTA combination groups, the SR was removed partially or completely and no statistical significance. This study demonstrated that in order to remove the SR should be used EDTA solution for final irrigation in the root canal, regardless of the technique in each of the three.
authors: Department of Endodontics, Faculty of Dentistry, Inonu University, Malatya, Turkiye.
authors: Fuat
authors: F
authors: Ahmetoglu
authors: Department of Endodontics, Faculty of Dentistry, Inonu University, Malatya, Turkiye.
authors: Ali
authors: A
authors: Keles
authors: Department of Restorative Dentistry, Faculty of Dentistry, Inonu University, Malatya, Turkiye.
authors: Muhammet
authors: M
authors: Yalcin
authors: Department of Endodontics, Faculty of Dentistry, Inonu University, Malatya, Turkiye.
authors: Neslihan
authors: N
authors: Simsek
keywords: Conventional needle irrigation; EndoVac system; passive ultrasonic irrigation; scanning electron microscopy; smear layer