since the introduction of engine-driven nickel-titanium (niti) instruments, attempts have been made to minimize or eliminate their inherent defects, increase their surface hardness/flexibility and also improve their resistance to cyclic fatigue and cutting efficiency. the various strategies of enhancing instrument surface include ion implantation, thermal nitridation, cryogenic treatment and el...

Rotary root canal instruments manufactured from nickel-titanium alloy have proved to be a valuable adjunct for root canal therapy. Over the past two decades, instrument design has been considerably modified; progress has been made in manufacturing, as well as alloy processing. Clinical procedures and ideal working parameters are still being refined as new instruments continue to be introduced t...

This report introduces a novel technique that allows a safe and predictable canal negotiation, creation of a glide path and canal preparation with reciprocating nickel-titanium or stainless steel engine-driven instruments in canals where the use of rotary and the newly developed reciprocating instruments is contraindicated. In this novel technique, the instruments are used in reciprocating moti...

It has been recommended by the World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) that rigorous decontamination protocols be used on surgical instruments that have been exposed to tissue possibly contaminated with Creutzfeldt-Jakob disease (CJD). This study was designed to examine the effects of these protocols on various types of surgical instruments. The most...

A new manufacturing method of twisting nickel titanium wire to produce rotary nickel titanium (RNT) files has recently been developed. The aim of the present study was to evaluate whether the new manufacturing process increased the angular deflection of RNT files, by comparing instruments produced using the new manufacturing method (Twisted Files) versus instruments produced with the traditiona...

Soon after the founding of the Microsurgical Instrumentation Research Association (MICRA) in 1971, it was decided to investigate the possible use of titanium and its alloys in the production of surgical instruments suitable for use with the microscope. After an analysis of surgical instruments available at that time, it was clear to us that modifications to existing designs were required. Most ...

Nickel-titanium engine-driven rotary instruments are used increasingly in endodontic practice. One frequently mentioned problem is fracture of an instrument in the root canal. Very few studies have been conducted on torsional characteristics of these instruments, and none has been done under dynamic conditions. The purposes of this study were to measure the torque generated and the apical force...

OBJECTIVE The objective of this study was to compare the smear layer formed on root canal walls during canal preparation of extracted human teeth by Twisted, Mtwo, and ProTaper rotary nickel titanium instruments. MATERIALS AND METHODS Sixty single rooted human premolar teeth with root curvature <25(0) were selected and randomly divided into three Groups (n= 20 teeth per Group). Three types of...