The microstructural evolution of Ni-20 pct Cr wires was studied during pack cementation where Al and Ti, with and without prior cementation with Mo, are deposited to the surface of the NiCr wires and subsequently homogenized in their volumes. Mo deposition promotes the formation of Kirkendall pores and subsequent co-deposition of Al and Ti creates a triple-layered diffusional coating on the wir...

Abstract: In the present study the effect of thermomechanical treatment (cold work and annealing) on the transformation behavior of NiTi shape memory alloys was studied. Differential scanning calorimetry was used to determine transformation temperature and its relation to precipitates and defects. Three alloys including Ti-50.3at.% Ni, Ti-50.5at.% Ni (reclamated orthodontic wires) and 50.6at...

UNLABELLED The relationship between orthodontic force and friction produced from an archwire and brackets affects the sliding of the wire in the leveling stage. OBJECTIVE The purpose of this study was to evaluate the relationship between force and friction in a small esthetic nickel-titanium (Ni-Ti) wire. MATERIAL AND METHODS Five esthetic wires (three coated and two plated) and two small, ...

AIM To determine how instrument design affects the fatigue life of two nickel-titanium (Ni-Ti) rotary systems (Mtwo and ProTaper) under cyclic fatigue stress in simulated root canals. METHODOLOGY Cyclic fatigue testing of instruments was performed in stainless steel artificial canals with radii of curvature of 2 or 5 mm and an angle of curvature of 60 degrees . A total of 260 instruments were...

Avascular necrosis of the lunate bone (Kienböck disease) is caused by loss of blood supply of the bone. This study aimed to evaluate the efficacy and safety of a novel nickel-titanium (Ni-Ti) memory alloy arthrodesis concentrator in the treatment of this disease.A consecutive 24 patients with stage IIIb aseptic lunate necrosis were treated with scapho-trapezio-trapezoeid (STT) arthrodesis using...

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Metallic piercing which have lack of resistance to sweat corrosion might be able to release metallic ions in the local tissue producing adverse effects in the human body, including allergic contact dermatitis (ACD). The aim of this study was double: 1) the metallic characterization of piercings and 2) the release of metals (Al, Co, Cr, Cu, Fe, Ir, Mn, Ni, Pd, Pt, Rh, Ti, V and Zn) in artificial...

OBJECTIVES The aim of this study was to compare the dimensional standard of several nickel-titanium (Ni-Ti) rotary files and verify the size conformity. MATERIALS AND METHODS ProFile (Dentsply Maillefer), RaCe (FKG Dentaire), and TF file (SybronEndo) #25 with a 0.04 and 0.06 taper were investigated, with 10 in each group for a total of 60 files. Digital images of Ni-Ti files were captured und...

Planning target volumes (PTV) in fractionated radiotherapy still have to be outlined with wide margins to the clinical target volume due to uncertainties arising from daily shift of the prostate position. A recently proposed new method of visualization of the prostate is based on insertion of a thermo-expandable Ni-Ti stent. The current study proposes a new detection algorithm for automated det...