introduction: this study investigated the fatigue and fracture modes of race and protaper rotary instruments. materials & methods: fatigue resistance was evaluated by rotating the files 30 ° or 60 ° and with 2 or 5mm radius of curvature. race taper 06 size 25 and protaper f1 files (n=40) were used. the number of rotations to failure was analyzed by two-way anova and independent sample     t-tes...

background: root canal cleaning is an important step in endodontic therapy. in order to develop better techniques, a new generation of endodontic instruments has been designed. the aim of this study was to compare the effectiveness of manual k-files (mani co, tokyo, japan) and two rotary systems–mtwo (dentsply-maillefer, ballaigues, switzerland) and protaper (vdw, munich, germany)–for root cana...

INTRODUCTION New designs and alloys have been developed to increase cyclic fatigue (CF) resistance of rotary files. The aim of this study was to compare CF resistance of ProTaper Universal (PTU; Dentsply Tulsa Dental, Tulsa, OK) and ProTaper Next (PTN, Dentsply Tulsa Dental) instruments at different points of curvature. METHODS A total of 420 files (240 PTU, S1, F1, F2, and F3 and 180 PTN, X1...

Background and aim: The purpose of this study was to evaluate the effect of autoclave sterilization on the fracture rate of ProTaper instruments (ex vivo). Materials and methods: One hundred shaping and finishing ProTaper instruments were used in a crown – down technique for cleaning and shaping the mesial canals of extracted mandibular molars using 5.25% NaOCl for irrigation. In the e...

INTRODUCTION The effect of smear layer and debris on the success rate of endodontic treatment has not yet been definitely determined. So the present study was aimed to evaluate the amount of smear layer and debris on the canal walls prepared with a combination of hand and rotary ProTaper technique using NaOCl and ethylenediaminetetraacetic acid (EDTA) alternately as root canal irrigants using s...