UNLABELLED Misfit at the abutment-prosthetic cylinder interface can cause loss of preload, leading to loosening or fracture of gold and titanium screws. OBJECTIVES To evaluate the influence of screw type, alloy, and cylinder position on marginal fit of implant frameworks before and after laser welding. METHODS After Estheticone-like abutments were screwed to the implants, thirty plastic pro...

Rene88 samples were investigated using atom probe tomography and x-ray diffraction using a monochromated synchrotron beam with different energy values to determine the preferred site occupancy of various alloying elements within the ordered γ’ precipitates. Samples were solutionized and cooled at 24 degree C/min with subsequent aging at 760 degrees C. The synchrotron-based x-ray diffraction res...

Metal-induced allergic contact dermatitis (ACD) is expressed in a wide range of cutaneous reactions following dermal and systemic exposure to products such as cosmetics and tattoos, detergents, jewellery and piercing, leather tanning, articular prostheses and dental implants. Apart from the well known significance of nickel in developing ACD, other metals such as aluminium, beryllium, chromium,...

Introduction: Metal prostheses in patients affect the radiotherapy dose distribution. Metal prostheses with high density and atomic number cause major changes in scattering and attenuation of radiation. The present study aims to assess the impact of metal knee prosthesis with various dimensions and materials on radiotherapy dose distribution. Material and Methods: In this research, the Varian L...

Aim: There is little information considering the framework association between cast clasps and attachments. The aim of this study was to evaluate the retention strength of frameworks match circumferential clasps and extra resilient attachment cast in three different alloys (cobalt-chromium, nickel-chromium titanium and commercially pure titanium), using two undercut (0.25 and 0.75 mm) and consi...

Chromium is a naturally occurring, toxic heavy metal used in many industrial processes. The U.S. Department of Labor's Occupational Safety and Health Administration has established specific limits for occupational exposure levels of chromium and guidelines for medical surveillance of individuals who have been exposed to chromium. The author presents a case in which a 54-year-old man who had bee...

The effect of prior air exposure on rupture life of superalloys is reported. Oxygen is identified as a damaging species leading to severe losses in both rupture life and ductility. Similar embrittlement is observed in pure nickel and a mechanism is proposed in terms of reduced grain boundary mobility. Two cobalt base alloys and an oxide dispersion strengthened nickel base alloy do not embrittle...

In order to determine the magnitude of temperature increases in resurfaced hips, temperature sensors were placed percutaneously in both hip joints of 12 volunteer patients who had 1 or both joints resurfaced. Temperature recordings were made with patients at rest (baseline) and after patients walked for 20 and 60 minutes. The hip resurfacing procedures were performed 12 to 36 months prior to th...