introduction: preserving the apical root structure during cleaning and shaping of the canal has always been a challenge in endodontics particularly when the root canals are curved. the purpose of this in vitro study was to compare the apical transportation induced by the reciproc and biorace rotary systems in preparing the mesiobuccal root canal of the human maxillary molars. materials and meth...

AIM The aim of this study was to measure the increase in root canal surface area and canal transportation after biomechanical preparation at 1, 3, and 5 mm short of the apex with three different rotary systems in both continuous rotary and reciprocating rotary motions. MATERIALS AND METHODS Sixty freshly extracted human mandibular molars with mesial root canal curvatures between 20° and 30° w...

OBJECTIVES To determine the actual revolutions per minute (rpm) values and compare the cyclic fatigue life of Reciproc (RPC, VDW GmbH), WaveOne (WO, Dentsply Maillefer), and TF Adaptive (TFA, Axis/SybronEndo) nickel-titanium (NiTi) file systems using high-speed camera. MATERIALS AND METHODS Twenty RPC R25 (25/0.08), 20 WO Primary (25/0.08), and 20 TFA ML 1 (25/0.08) files were employed in the...

The aim of this study was to evaluate the effectiveness of manual and rotary instrumentation techniques for removing root fillings after different storage times. Twenty-four canals from palatal roots of human maxillary molars were instrumented and filled with gutta-percha and zinc-oxide eugenol-based sealer (Endofill) , and were stored in saline for 6 years. Non-aged control specimens were trea...

introduction: pulpectomy is the preferred treatment for restorable primary teeth with symptomatic irreversible pulpitis or periradicular lesion. considering the rather new application of rotary files for pulpectomy of primary teeth, the aim of this study was to compare the cleaning efficacy and instrumentation time of hand k-files and mtwo rotary system for preparation of human primary molars. ...

The use of reciprocating movement (RM) was claimed to increase the resistance of nickel-titanium (NiTi) file to fatigue in comparison to continuous rotation (CR). Recently two new brands of NiTi file have been marketed for use in a RM mode. The purpose of this study was to compare the cyclic fatigue resistance and torsional resistance of these two files; Reciproc and WaveOne. Cyclic fatigue tes...

AIM The purpose of this study is to achieve an effective method to remove root canal filling material from the root canal system. The study, thus, aims to evaluate the efficacy of the cleaning ability of two different rotary Ni-Ti systems; ProTaper Retreatment files and RaCe System compared to hand instrumentation with Hedstrom files for the removal of gutta-percha during retreatment. MATERIA...

Since the introduction of nickel titanium (NiTi) to field endodontics, it paved way for fast and reliable root canal instrumentation. Rotary instruments are solely manufactured from NiTi alloy, due its favorable mechanical physical properties such as flexibility cutting efficiency. The main problem with rotary is their high fatigue susceptibility, unexpected incident instrument separation insid...

Introduction: Although rotary instrumentation has been widely studied in permanent dentition, it is a rather new field of study concerning primary teeth. Purpose: We aimed to evaluate apical displacement and time needed for instrumentation of root canals of primary molars by manual and rotary techniques. Materials and Methods: Root canals of 144 extracted first and second primary maxillary mola...

This study evaluated temperature changes during passive ultrasonic irrigation. Root canals of three extracted maxillary canines were enlarged to size #45. Thermocouples were mounted 3, 6, and 9 mm from the apical foramen. Teeth were placed in a water bath at 37 degrees C. Distilled water (20 degrees C) was continuously delivered through an ultrasonic unit (group 1) or deposited into the root ca...