introduction : to evaluate the efficacy of niti mechanical rotary instrumentation and hedstrom file for gutta-percha/sealer removal computed tomography (ct) was utilized in vitro . materials and methods: thirty extracted human single rooted teeth, each with a single canal were selected. the samples were decoronated with a double faced diamond disk to have 17-mm root; teeth roots were instrument...

Abstract In this study, a coupling model of fluid-conveying pipes made functionally graded materials (FGMs) with NiTiNOL-steel (NiTi-ST) for vibration absorption is investigated. The responses the FGM pipe NiTi-ST are studied by Galerkin truncation method (GTM) and harmonic balance (HBM). solutions numerical results consistent. Also, linearized stability structure determined. effects parameters...

Large changes in hysteresis are reported as a function of applied stress under thermal cycling experiments in NiTi single crystals. In the low Ni alloy the thermal hysteresis expanded with increasing stress while in the high Ni alloy the thermal hysteresis contracted with increasing stress. The results in both cases meet the limit obtained from Differential Scanning Calorimetry at zero stress. ...

Nickel–titanium (NiTi) is a shape-memory alloy, type of material whose name derived from its ability to recover original shape upon heating certain temperature. NiTi falls under the umbrella metallic materials, offering high superelasticity, acceptable corrosion resistance, relatively low elastic modulus, and desirable biocompatibility. There are several challenges regarding processing machinab...

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...

Nickel-titanium (NiTi) instruments are commonly used for shaping the root canal system in endodontic practice. They are more flexible and have better cutting efficiency than conventional stainless steel files. The superelasticity of NiTi rotary files allows the clinicians to produce the desirable tapered root canal form with a reduced tendency to canal transportation and instrument fracture. Hy...

BACKGROUND Efforts to improve the performance of rotary NiTi instruments by enhancing the properties of NiTi alloy, or their manufacturing processes rather than changes in instrument geometries have been reported. The aim of this study was to compare in-vitro the shaping ability of three different rotary nickel-titanium instruments produced by different manufacturing methods. METHODS Thirty s...

OBJECTIVE The aim was to evaluate the alteration of the deactivation forces of the most commonly used nickel-titanium wires under long-lasting oral cavity environmental influence. MATERIALS AND METHODS Randomized in vitro and in vivo trials of 540 pieces of orthodontic archwires, NeoSentalloy®, Copper NiTi® 35°C and Titanol Superelastic(®), round (0.016 inch), and rectangular (0.016 × 0.022 i...