introduction : the aim of the present study was to comparatively evaluate the physical surface changes and incidence of separation in rotary nickel-titanium (niti) instruments using scanning electron microscope (sem). methods and materials: a total number of 210 freshly extracted human maxillary and mandibular first molars were selected and distributed between three groups. three different syst...

Abstract: Permanent magnetic linear motors(PMLMs) are easier to accelerate and achieve higher precision than rotary motors. Hence, they have a broad range of applications in the manufacturing industry and other motion control fields. Owing to the structural variation, however, the models of permanent magnet linear motors and rotary motors are different. As a result, their motion control systems...

This clinical report introduces a method for safe retrieval of a broken implant abutment screw. A reverse-tapping rotary instrument has been introduced in the market and is widely used to retrieve broken screws; however, it is difficult to use the rotary instrument unless an access hole for engagement of the rotary instrument is positioned directly on the center of the top of the broken screw r...

ARTICLE INFO ABSTRACT Article Type: Original Article Introduction: The aim of this study was to compare several metallurgic properties of Neoniti instrument with four other commonly used endodontic rotary files. Methods and Materials: Neoniti A1 (25/0.08), RaCe (25/0.06), Mtwo (25/0.06), Twisted file (25/0.06) and ProTaper Next X2 (25/0.06) were examined by differential scanning calorimetry (DS...

INTRODUCTION The purpose of this study was to evaluate the efficacy of three methods in removal of Resilon/new Epiphany self-etch (SE) soft resin endodontic obturation system. MATERIALS AND METHODS Thirty extracted single rooted human teeth were prepared for endodontic treatment and obturated with Resilon/Epiphany SE. The roots were randomly divided into three groups; group 1 roots were retre...

Objective: To compare the straightening of root canal curvature, the apical transportation, the loss of working length and the working time using two rotary systems. Study design: Sixty buccal root canals with angles of curvature between 30 to 99o were instrumented with Mtwo and Twisted File rotary instruments. A series of preand post-operative radiographs were superimposed to determine the str...

There are two main systems that can be used to coil and uncoil the wires of a wire-driven parallel robots: a rotary motor that turns a drum on which the wire is coiled or a linear motor with a pulley system. The rotary category may be divided into two sub-categories: the system with a spiral guide for the coiling, allowing only layer for the wire and the system without guide, that allows for se...

Problem statement: The rotary inverted pendulum system was a highly nonlinear model, multivariable and absolutely unstable dynamic system. It was used for testing various design control techniques and in teaching modern control. The objectives of this study were to: (i) Develop a real rotary inverted pendulum which derived the mechanical model by using Euler-Lagrange and (ii) Design controller ...

The removal of necrotic and vital pulp substrates microorganisms their toxins from the root canal system (RCS) has been found to be basis for a successful endodontic treatment. In this study, our aim was evaluate effect passive ultrasonic irrigation (PUI) on elimination organic remnant tissue infected, narrow curved mandibular canals during instrumentation. For purpose, mesiobuccal first molars...