INTRODUCTION To evaluate and compare the amount of time required by three rotary NiTi instruments in removing gutta-percha from root canal during retreatment with hand file as control. MATERIALS AND METHODS Eighty human mandibular premolars with single straight root canals were prepared and obturated by cold lateral condensation with gutta-percha and AH Plus sealer. After two weeks, the 80 te...

Screw-in effect is one of the unintended phenomena that occurs during the root canal preparation with nickel-titanium rotary files. The aim of this study was to compare the screw-in effect among various nickel-titanium rotary file systems. Six different nickel-titanium rotary instruments (ISO 20/.06 taper) were used: K3 (SybronEndo, Glendora, CA, USA), Mtwo (VDW GmbH, München, Germany), NRT wit...

introduction: one of the most common complications of root canal treatment is postoperative pain. the aim of the present clinical trial was to compare the severity of postoperative pain after root canal preparation with race rotary system and hand k-flexofile. methods and materials: a total of 96 mandibular first and second molars were divided into two groups ( n =48) based on root canal prepar...

PURPOSE This study compared the cutting area, instrumentation time, root canal anatomy preservation and non-instrumented areas obtained by F360(®), Mtwo(®), RaCe(®) and Hyflex(®) files with ISO size 35. MATERIAL AND METHODS 120 teeth with a single straight root and root canal were divided into 4 groups. Working length was calculated by using X-rays. The teeth were sectioned with a handpiece a...

BACKGROUND Complete removal of old filling material during root canal retreatment is fundamental for predictable cleaning and shaping of canal anatomy. Most of the retreatment methods tested in earlier studies have shown inability to achieve complete removal of root canal filling. Therefore the aim of this investigation was to assess the efficacy of three different rotary nickel titanium retrea...

The purpose of this investigation was to compare centring ratio of ProTaper and Mtwo rotary systems. 60 mandibular molar teeth which had 25, 30 and 35 degree curvature in mesio-buccal root canal were used. Group 1 had 25°, Group 2 had 30°, and Group 3 had 35° curvatures. The roots were sectioned horizontally at 2 mm away from the apex. The apical region was then observed under a stereo-microsco...

OBJECTIVE To compare the disinfecting efficacy of the sodium hypochlorite irrigation by root canal preparation with stainless steel hand files, taper 0.02 and nickel-titanium Mtwo files with taper 0.04-0.06. STUDY DESIGN 40 extracted human teeth were sterilized, and then inoculated with Enterococcus faecalis (ATCC 29212). After 6 day incubation time the root canals were prepared by hand with ...

Aim: To compare the efficacy of various instrumentation techniques for removing obturating material from root canals using Cone Bean Computed Tomography (CBCT). Materials and Methods: Thirty extracted human premolar teeth, each with a single canal were selected. The root canals were prepared upto F4 ProTaper file and obturated with corresponding gutta percha cone. Teeth were divided into three ...

AIM The aim of the present study was to electrochemically evaluate corrosion resistance of RaCe and Mtwo files after repeated sterilization and preparation procedures. STUDY DESIGN A total of 450 rotary files were used. In the working groups, 72 files from each file type were distributed into 4 groups. RaCe and Mtwo files were used to prepare one root canal of the mesial root of extracted hum...

UNLABELLED Gram-negative bacteria play an essential role in endodontic infections because they have virulence factors such as endotoxin. Due to its potential cytotoxic activity, special attention has been given to the removal/neutralization of this endotoxin in the root canal system. OBJECTIVE The aim of this study was to evaluate the influence of the apical enlargement size (AES) by using ro...