Papers by Keyword: Acrylic Cement

Abstract: Commercially available acrylic cement which has been popular in orthopaedics in the nineties of the recent century (SIMPLEX P, manufactured by HOWMEDICA LIMERICK) was used in the study. The choice of this material was caused by the fact that the average period of operation of cement prostheses in human body amounts to ca. 12 years and large percentage of prostheses implanted in this period is destabilized in the bone. The investigations focused on assessment of changes in strength parameters of PMMA used in human body over a period of 10 years and their effect on prosthesis loosening. In order to determine differences in strength parameters of the cement, directly after polymerization and after a particular period of use in human body, a series of tests were carried out, aimed at determination of the effect of aggressive environment inside human body and fatigue load which results from human motor activity on changes in strength parameters in PMMA. PMMA samples (30 days after polymerization, stored in saline solution) and the samples removed from human body due to aseptic loosening were used for comparison of strength. Due to a very complex character of operation and specific load, were tested in order to determine the dynamic properties by means of DMTA method, thus to determine the storage modulus E’ and the mechanical loss factor tgδ, responsible for dispersion of mechanical energy.

Abstract: Polymer-ceramic composites based on polymethyl methacrylate are widely used in orthopaedics as suture materials and fixation devices due to their biocompatibility and ability to support bony growth (osteoconductive) and also bone bioactive (to form a calcium phosphate layer on its surface). The aim of this study is to compare the microstructure, bioactivity and biocompatibility of new acrylic cement containing silver and collagen coated, with a comercial one, by in vitro study in simulated body fluid. In order to evaluate the properties of the surface layer, SEM microscopy and ATR-FTIR spectroscopy are used. The results indicates that both silver content and the presence of collagen layer favourise the mineralisation process at the surface.