introduction : removal of root filling materials is one of the key steps in success of root canal retreatment. the purpose of this study was to evaluate the efficacy of h-file and protaper with or without chloroform in the removal of gutta-percha during retreatment of mandibular premolars. materials and methods: sixty mandibular premolars with one canal, and curvatures less than 30 degrees were...

apical extrusion of debris and irrigants during cleaning and shaping of the root canal is one of the main causes of periapical inflammation and postoperative flare-ups. the purpose of this study was to quantitatively measure the amount of debris and irrigants extruded apically in single rooted canals using two reciprocating and one rotary single file nickel-titanium instrumentation systems.sixt...