RESUMO
This article focuses on obtaining ultra high molecular weight polyethylene (UHMWPE) material reinforced with functionalized single-walled carbon nanotubes (f-SWCNTs) and the manufacturing of unicompartmental knee implants via Single-Point Incremental Forming process (SPIF). The physicochemical properties of the developed UHMWPE reinforced with 0.01 and 0.1 wt% concentrations of f-SWCNTs are investigated using Raman and Thermogravimetic Analysis (TGA). Tensile mechanical tests performed in the nanocomposite material samples reveal a 12% improvement in their Young's modulus when compare to that of the pure UHMWPE material samples. Furthermore, the surface biocompatibility of the UHMWPE reinforced with f-SWCNTs materials samples was evaluated with human osteoblast cells. Results show cell viability enhancement with good cell growth and differentiation after 14 incubation days, that validates the usefulness of the developed nanocomposite material in the production of hip and knee artificial implants, and other biomedical applications.
Assuntos
Prótese do Joelho , Nanotubos de Carbono , Humanos , Teste de Materiais , Polietilenos , Propriedades de SuperfícieRESUMO
This article reviews certain practical aspects of retrieval analysis for motion preserving spinal implants and periprosthetic tissues as an essential component of the overall revision strategy for these implants. At our institution, we established an international repository for motion-preserving spine implants in 2004. Our repository is currently open to all spine surgeons, and is intended to be inclusive of all cervical and lumbar implant designs such as artificial discs and posterior dynamic stabilization devices. Although a wide range of alternative materials is being investigated for nonfusion spine implants, many of the examples in this review are drawn from our existing repository of metal-on-polyethylene, metal-on-metal lumbar total disc replacements (TDRs), and polyurethane-based dynamic motion preservation devices. These devices are already approved or nearing approval for use in the United States, and hence are the most clinically relevant at the present time. This article summarizes the current literature on the retrieval analysis of these implants and concludes with recommendations for the development of new test methods that are based on the current state of knowledge of in vivo wear and damage mechanisms. Furthermore, the relevance and need to evaluate the surrounding tissue to obtain a complete understanding of the biological reaction to implant component corrosion and wear is reviewed.