Objective: The welding process involves metal ions capable of causing cell lysis. In view of this fact, the aim of this study was to test the hypothesis that cytotoxicity is present in different types of alloys (CrNi, TMA, NiTi) commonly used in orthodontic practice when these alloys are subjected to electric spot welding. Methods: Three types of alloys were evaluated in this study. Thirty-six ...

NiTi foams are unique among biocompatible porous metals because of their high recovery strain (due to the shape-memory or superelastic effects) and their low stiffness facilitating integration with bone structures. To optimize NiTi foams for bone implant applications, two key areas are under active study: synthesis of foams with optimal architectures, microstructure and mechanical properties; a...

One of the main issues with the use of nickel titanium alloy (NiTi) implants in cardiovascular implants (stents) is that these devices must be of very high quality in order to avoid subsequent operations due to failing stents. For small stents with diameters below ca. 2 mm, however, stent characterization is not straightforward. One of the main problems is that there are virtually no methods to...

BACKGROUND This study aimed to compare superelastic and heat-activated nickel-titanium orthodontic wires' surface morphology and potential release of nickel ions following exposure to oral environment conditions. METHODS Twenty-four 20-mm-length distal cuts of superelastic (NiTi Force I®) and 24 20-mm-length distal cuts of heat-activated (Therma-Ti Lite®) nickel-titanium wires (American Ortho...

OBJECTIVES The purpose was to investigate the preference and usage technique of NiTi rotary instruments and to retrieve data on the frequency of re-use and the estimated incidence of file separation in the clinical practice among general dentists. MATERIALS AND METHODS A survey was disseminated via e-mail and on-site to 673 general dentists. The correlation between the operator's experience o...

Thirteen patients already scheduled for surgery for repair of prosthetic paravalvular regurgitation underwent intraoperative real time two-dimensional transesophageal echocardiography (2D TEE) and live/real time three-dimensional transesophageal echocardiography (3D TEE). In all patients, 3D TEE was able to provide more information regarding the location and size of the paravalvular defect as c...

The influence of body composition, resting metabolic rate (RMR), and sex on variation in total energy expenditure (TEE) was examined by using meta-analysis (13 published studies in a total of 162 adults). TEE (10.9 +/- 3.2 MJ/d) was significantly correlated with body mass (BM; weighted mean converted r = 0.68, P < 0.05) and resting metabolic rate (RMR; weighted mean converted r = 0.66, P < 0.05...

BACKGROUND quantification of mitral regurgitation severity with 2-dimensional (2D) imaging techniques remains challenging. The present study compared the accuracy of 2D transesophageal echocardiography (TEE) and 3-dimensional (3D) TEE for quantification of mitral regurgitation, using MRI as the reference method. METHODS AND RESULTS two-dimensional and 3D TEE and cardiac MRI were performed in ...

In the clinical practice, it is much more efficient to use NiTi rotary files compared to hand instrumentation. However, misuse of NiTi rotary files can result in procedural errors such as transportation, ledge, perforation, and file separation. Generally, following suggestions could be considered to avoid these errors. 1. Enlarge the coronal half of the root canal before preparing the apical pa...