Chemomechanical preparation of the root canal includes both mechanical instrumentation and antibacterial irrigation, and is principally directed toward the elimination of micro-organisms from the root canal system. A variety of instruments and techniques have been developed and described for this critical stage of root canal treatment. Since their introduction in 1988, nickel-titanium (NiTi) ro...

An experimental set up consisting of an upper typodont with ivorine teeth was employed. It was fitted with the Begg brackets. Rectangular wire sectionals in 0.016"x 0.022", 0.017" x 0.025", 0.018" x 0.025" and 019" x 0.025" sizes and made of Stainless Steel, Braided Stainless Steel, Superelastic NiTi, Braided NiTi, Copper NiTi, a -Titanium and BTitanium were tested. The MAA and the four spur to...

The last decade has been witness to phenomenal growth in endodontic technology. The introduction of these new technologies has resulted in endodontics becoming easier, faster and most importantly, better. Principal among these is Nickel Titanium (NiTi) rotary instrumentation that results in consistent, predictable, and reproducible shaping. The purpose of this article is to review the design fe...

NiTi instrument separation is a serious concern in endodontic therapy. The analysis of NiTi files after torsional fracture reveals that the majority of torsional separations occur in the last mm. of the files and in the files with lower taper and/ or diameter. Consequentely, the tip of the smaller files presents the higher risk of torsional fracture and should be protected using low torque moto...

Since the end of the nineteenth century, automated root canal instrumentation has been available, but systems had many problems. The challenges of increased canal blockage, instrument breakage, and insufficient canal debridement were related to the use of stainless steel instruments and have been dramatically improved with the introduction of nickel-titanium (NiTi) files. The first useable NiTi...

NiTi is the most used shape-memory alloy; nonetheless, a lack of understanding remains regarding the associated structures and transitions, including their barriers. Using a generalized solid-state nudged elastic band method implemented via density-functional theory, we detail the structural transformations in NiTi relevant to shape memory: those between a body-centered orthorhombic (bco) groun...

This work focuses on application of the laser forming process to NiTi shape memory alloys. While all NiTi shape memory alloys exhibit both superelasticity and the shape memory effect, this study is restricted to a temperature range over which only the superelastic effect will be active. Specifically, this work addresses laser forming induced macroscopic bending deformations, postprocess residua...

This paper presents a comparative theoretical study of the performance of a set of controllers for improving the speed of actuators based on shape memory alloys (SMAs), especially on Nitinol (NiTi). To prevent overheating and thermal fatigue, these controllers take into account the maximum heating current at which a NiTi element can safely be heated. The thermal behaviour of NiTi is first model...

The transformation behaviour of AA2124 alloys reinforced NiTi particulates of 10 vol pct and 20 vol pct has been studied by differential scanning calorimetry (DSC), thermoelectric power (TEP) and internal friction (IF). Addition of NiTi particulates increase the damping capacity as well as the precipitation kinetics of AA2124 composites with respect to the base AA2124. Heat treatments performed...