The purpose of this study was to investigate torque and angle of rotation at fracture of new and used.06 ProFile instruments. ProFile sizes 15 to 40 were tested according to American National Standards Institute/American Dental Association Specification #28. Thirty new and used instruments were tested for each size. An analysis of variance was used to compare the torque and angle of rotation at...

The process of direct two-proton decay of nuclei with Z 22-28 on the proton drip line is considered. On the basis of new Od3t2 Offi2 -shell-model mass extrapolations, '9Ti, 42Cr, 45Fe, Ni, and Ni are found to be bound to single-proton decay but unbound to two-proton decay. New estimates of the spectroscopic factors and lifetimes have been made. The decays of Ti, Fe, and Ni are found to be promi...

An intermetallic nickel-titanium alloy, 60NiTi (60wt%Ni, 40wt%Ti), is shown to be a promising candidate tribological material for space mechanisms. 60NiTi offers a broad combination of physical properties that make it unique among bearing materials. 60NiTi is hard, electrically conductive, highly corrosion resistant, readily machined prior to final heat treatment, and is non-magnetic. Despite i...

Reindeer antler was studied for its possible use as a bone implant material. A molecular biological study showed that antler contains a growth factor promoting bone formation. Ectopic bone formation assay showed that antler is not an equally effective inducer as allogenic material. Ectopic bone formation assay was optimised for biocompatibility studies of orthopaedic NiTi implants. Ti-6Al-4V an...

T he last 10 years have 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. Principle among these is nickel titanium rotary instrumentation that results in consistent, predictable, and reproducible shaping. This predictability of shaping has not only influenced ...

f bstract canning electron microscopy (SEM) and differential canning calorimetric (DSC) studies were utilized to nvestigate surface and microstructure of two brands of otary nickel-titanium (NiTi) endodontic instruments, in he as-received condition and after subjection to 1, 6, nd 11 sterilization cycles. A total of 66 ProFile (n 3) and Flexmaster (n 33) files were examined. SEM bservations ind...

The superelastic material Nitinol, a nearly equiatomic alloy of nickel and titanium, is rapidly becoming one of the most important metallic implant materials in the biomedical industry, especially for the fabrication of endovascular stents. The manufacture of these stents, and countless other Nitinol products, originates from various forms of raw material such as tube, sheet or rod. However, de...

The dependence of grain orientation on stress-induced martensitic transformation in superelastic, polycrystalline Nickel-Titanium sheet was examined at the microstructural length scale. Full-field strains, indicative of transformation extent, were characterized in fields of view of nominally 100 μm x 100 μm using a custom combination of scanning electron microscopy with distortioncorrected digi...

This paper describes an experimental study of stress-induced martensitic phase transformation in the SMA Nickel-Titanium. The rich local thermo-mechanical interactions that underlie transformation are examined using three-dimensional Digital Image Correlation (strain fields) and infrared imaging (thermal fields). We quantify the complex local interactions between released/absorbed latent heat a...

The clinical endodontic breakthrough was progressing from utilizing a long series of stainless steel (SS) hand files and several rotary Gates Glidden drills to integrating nickel titanium (NiTi) files for shaping canals. Regardless of the methods utilized, the mechanical objectives for canal preparation were brilliantly outlined almost 40 years ago by Dr. Herbert Schilder.1 When properly perfor...