title: [Scanning electron microscopy studies of morphologic changes in ultra-high molecular weight polyethylene materials after various processing steps].
abstract: Scanning electron microscopic (SEM) studies were carried out on various orthopaedic implants made of ultra-high molecular weight polyethylene (UHMWPE). Both non-sterilized and gamma-sterilized machined (milled) implants were used. Milled implants showed significant surface irregularities, and cross-sections also revealed irregularities in deeper layers of the polyethylene. In gamma-sterilized implants, cracks measuring 10-30 microns in length were found at a depth of 1.5 to 2.5 mm. Crater-like defects were also occasionally seen.
  
  
  CONCLUSIONS
  On the basis of these findings, direct compression moulding and a sterilization process in which oxygen is eliminated can be recommended as ways of improving the quality of UHMWPE used for orthopaedic implants.
authors: Klinik und Poliklinik für Allgemeine Orthopädie, Westfälische Wilhelms-Universität Münster.
authors: J
authors: J
authors: Jerosch
authors: S
authors: S
authors: Fuchs
authors: T
authors: T
authors: Schmidt
authors: R
authors: R
authors: Reichelt
mesh_terms: D006801:Humans; D007719:Knee Joint / Q000601:surgery; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008970:Molecular Weight; D010329:Patella / Q000601:surgery; D011095:Polyethylenes; D019736:Prostheses and Implants; D013499:Surface Properties
chemical_list: D011095:Polyethylenes
vernacular_title: Rasterelektronenmikroskopische Untersuchungen morphologischer Veränderungen am Werkstoff ultrahochmolekulares Polyethylen (UHMWPE) nach verschiedenen Bearbeitungsschritten.