The effect of very low concentrations of Vitamin E on the stability and mechanical behavior of UHMWPE remains unknown. We tested the hypothesis that the oxidation resistance of Vitamin E-blended UHMWPE would be influenced by trace doses of antioxidant, resin, and radiation treatment. Trace concentrations (< or =500 ppm w/w%) of alpha-tocopherol (Vitamin E) were blended separately with GUR 1020 ...

After the gamma-irradiation sterilization, the most widely used orthopaedic grade polymer bearing liner material for the total joint replacement, ultra-high molecular weight polyethylene (UHMWPE), degrades through the progressive in vivo oxidation. The oxidative degradation makes UHMWPE brittle and leads to reduction of its mechanical properties. In this study, the effect of the in vivo post-ir...

Ultra high-molecular weight polyethylene (UHMWPE) remains the most commonly used material in modern joint replacement prostheses. However, UHMWPE wear particles, formed as the bearing articulates, are one of the main factors leading to joint replacement failure via the induction of osteolysis and subsequent aseptic loosening. Previous studies have shown that the addition of antioxidants such as...

INTRODUCTION Artificial joints have been increasingly used in treatment of physically disabled people who have severely damaged joints. In artificial joint, ultra high molecular weight polyethylene (UHMWPE) has been usually employed as a buffer because of its very low friction coefficient, high wear resistance, high impact strength, and biocompatibility. [1]. When artificial joints were replace...

It has been suggested that the wear of ultra-high molecular weight polyethylene (UHMWPE) in total hip replacement is substantially reduced when the femoral head is ceramic rather than metal. However, studies of alumina and zirconia ceramic femoral heads on the penetration of an UHMWPE liner in vivo have given conflicting results. The purpose of this study was to examine the surface characterist...

During total hip arthroplasty, both the femoral and acetabular bearing surfaces are surgically replaced with metallic, polymeric, and/or ceramic components. Throughout the twentieth century, many different combinations of these materials have been proposed and examined as bearing surfaces for total hip arthroplasty. Metal-on-metal total hip replacements were first implanted by Wiles in the 1930...

The UHMWPE has a plastic behaviour but it is specified only the surface wear, unless the evaluation of the great importance of this behaviour of plasticity for the calculation of the depth of penetration. This work tries to demonstrate the fact that there are components of the wear by plastic deformation. Also, by this type of wear an explanation of smooth surface of the UHMWPE in the contact z...

When subjected to a monotonically increasing deformation state, the mechanical behavior of UHMWPE is characterized by a linear elastic response followed by distributed yielding and strain hardening at large deformations. During the unloading phases of an applied cyclic deformation process, the response is characterized by nonlinear recovery driven by the release of stored internal energy. A num...

Ultra-high molecular weight polyethylene (UHMWPE) is frequently employed in joint replacements because of its high biocompatibility; however, this material does not exhibit particularly strong wear performance, thus potentially reducing the longevity of such devices. Numerous techniques have been investigated to increase the resistance to wear of UHMWPE, but they are all based on expensive mach...