background and aims. the superiority of rotary systems has been reported in several clinical studies on permanent teeth. this study consisted of radiographic assessment and chair time of rotary instruments in the pulpectomy of primary second molar teeth. materials and methods. in this randomized controlled clinical study, 46 children, 3-6 years of age, were selected. the patients were divided r...

INTRODUCTION The purpose of this study was to compare the in vitro amount of apically extruded debris with new endodontic rotary nickel-titanium instruments. METHODS Sixty mandibular premolars were instrumented up to size 25 using ProTaper Universal (Dentsply Maillefer, Ballaigues, Switzerland), ProTaper Next (Dentsply Maillefer), Twisted File Adaptive (SybronEndo, Orange, CA), and HyFlex (Co...

Aim: To determine the centering ability of Twisted FileTM rotary system compared with ProTaper UniversalTM and ProFileTM rotary systems by evaluating preand postoperative cross-sectional images of the apical root canals third. Methods: Thirty mesiobuccal canals of human mandibular first molars were divided into three groups with 10 root canals each according to the instrument used: group 1, Pro...

OBJECTIVE Apical deviations are important factors in endodontic therapy, since they can cause the treatment failure. The aim of the present study was to determine the centering capacity of ProTaper Universal™, Twisted File™ and Revo-S® rotary systems using cone beam computed tomography analysis before and after the instrumentation of root canals. MATERIALS AND METHODS Thirty mesiobuccal roots...

AIM To evaluate ex vivo, apical bacterial extrusion associated with two reciprocating single-file systems (WaveOne and Reciproc) compared with a conventional multifile rotary system (BioRace). METHODOLOGY Forty-five human single-rooted mandibular incisors were used. Endodontic access cavities were prepared, and root canals were contaminated with an Enterococcus faecalis suspension. Following ...

In this paper, the characteristics of two rotary tables driven by worm gear and roller gear cam are measured and compared. The positioning accuracy and repeatability as specified in ISO 230-2 are measured together with the rotational fluctuation, backlash, friction torque, frequency response of the systems and also the influence of unbalance mass on rotational motion. Two rotary encoders which ...

MEMS (micro-electro-mechanical-systems) device has been a promising and fascinating topic in both mechanical and electrical engineering domains for decades with the revolutionary contributions to the contemporary micro-scale instruments especially for the micro-actuator and micro-sensor. Among the versatile material foundation to build up the MEMS device, silicon wafer is preferred to due to th...

OBJECTIVE This study has two aims: 1) to evaluate the apical transportation of the Wizard CD Plus and ProTaper Universal after preparation of simulated root canals; 2) to compare, with Adobe Photoshop, the ability of a new software (Regeemy) in superposing and subtracting images. MATERIAL AND METHODS Twenty five simulated root canals in acrylic-resin blocks (with 20º curvature) underwent cone...

Knowledge of droplet behavior is one of the most important criteria for determination of mass transfer kinetics for choosing the type of liquid-liquid extraction columns. Mean drop size data of dispersed phase droplets in continuous phase have been obtained for Various Rotary Agitated Liquid-Liquid Extraction Columns . The effects of operational variables such as mass transfer directions with a...