title: Comparison of the amount of apical debris extrusion associated with different retreatment systems and supplementary file application during retreatment process.
abstract: BACKGROUND
  The type of instrument affects the amount of debris extruded. The aim of this study was to compare the effect of retreatment systems and supplementary file application on the amount of apical debris extrusion.
  
  
  METHODS
  Forty-eight extracted mandibular premolars with a single canal and similar length were selected. The root canals were prepared with the ProTaper Universal system with a torque-controlled engine. The root canals were dried and were obturated using Gutta-percha and sealer. The specimens were randomly divided into four equal groups according to the retreatment procedures (Group 1, Mtwo retreatment files; Group 2, Mtwo retreatment files + Mtwo rotary file #30 supplementary file; Group 3, ProTaper Universal retreatment (PTUR) files; and Group 4, PTUR files + ProTaper F3 supplementary file). The extruded debris during instrumentation were collected into preweighed Eppendorf tubes. The amount of apically extruded debris was calculated by subtracting the initial weight of the tube from the final weight. Three consecutive weights were obtained for each tube.
  
  
  RESULTS
  No statistically significant difference was found in the amount of apically extruded debris between Groups 1 and 3 (P = 0.590). A significant difference was observed between Groups 1 and 2 (P < 0.05), and between Groups 3 and 4 (P < 0.05).
  
  
  CONCLUSIONS
  The use of supplementary file significantly increased the amount of apically extruded debris.
authors: Department of Endodontics, Faculty of Dentistry, Bülent Ecevit University, Zonguldak, Turkey.
authors: Ersan
authors: E
authors: Çiçek
authors: Department of Endodontics, Faculty of Dentistry, Bülent Ecevit University, Zonguldak, Turkey.
authors: Mustafa Murat
authors: MM
authors: Koçak
authors: Department of Endodontics, Faculty of Dentistry, Bülent Ecevit University, Zonguldak, Turkey.
authors: Sibel
authors: S
authors: Koçak
authors: Department of Endodontics, Faculty of Dentistry, Bülent Ecevit University, Zonguldak, Turkey.
authors: Baran Can
authors: BC
authors: Sağlam
keywords: Apical extrusion; retreatment; retreatment system; supplementary file