title: Physico-chemical characterization and the in vitro genotoxicity of medical implants metal alloy (TiAlV and CoCrMo) and polyethylene particles in human lymphocytes.
abstract: BACKGROUND
  The main objective of the present study was to investigate chemical composition and possible cyto/genotoxic potential of several medical implant materials commonly used in total hip joint replacement.
  
  
  METHODS
  Medical implant metal alloy (Ti6Al4V and CoCrMo) and high density polyethylene particles were analyzed by energy dispersive X-ray spectrometry while toxicological characterization was done on human lymphocytes using multi-biomarker approach.
  
  
  RESULTS
  Energy dispersive X-ray spectrometry showed that none of the elements identified deviate from the chemical composition defined by appropriate ISO standard. Toxicological characterization showed that the tested materials were non-cyto/genotoxic as determined by the comet and cytokinesis-block micronucleus (CBMN) assay. Particle morphology was found (by using scanning electron and optical microscope) as flat, sharp-edged, irregularly shaped fiber-like grains with the mean particle size less than 10µm; this corresponds to the so-called "submicron wear". The very large surface area per wear volume enables high reactivity with surrounding media and cellular elements.
  
  
  CONCLUSIONS
  Although orthopedic implants proved to be non-cyto/genotoxic, in tested concentration (10μg/ml) there is a constant need for monitoring of patients that have implanted artificial hips or other joints, to minimize the risks of any unwanted health effects.
  
  
  CONCLUSIONS
  The fractal and multifractal analyses, performed in order to evaluate the degree of particle shape effect, showed that the fractal and multifractal terms are related to the "remnant" level of the particles' toxicity especially with the cell viability (trypan blue method) and total number of nucleoplasmic bridges and nuclear buds as CBMN assay parameters.
authors.affiliation: Institute for Medical Research and Occupational Health, Mutagenesis Unit, 10000 Zagreb, Croatia. Electronic address: ggajski@imi.hr.
authors.forename: Goran
authors.initials: G
authors.lastname: Gajski
authors.forename: Zelimir
authors.initials: Z
authors.lastname: Jelčić
authors.forename: Višnja
authors.initials: V
authors.lastname: Oreščanin
authors.forename: Marko
authors.initials: M
authors.lastname: Gerić
authors.forename: Robert
authors.initials: R
authors.lastname: Kollar
authors.forename: Vera
authors.initials: V
authors.lastname: Garaj-Vrhovac
mesh_terms: D000497:Alloys / Q000009:adverse effects*; D001672:Biocompatible Materials / Q000009:adverse effects*; D002470:Cell Survival; D002478:Cells, Cultured; D002857:Chromium / Q000737:chemistry; D003035:Cobalt / Q000737:chemistry; D020552:Comet Assay; D048749:Cytokinesis; D004249:DNA Damage / Q000187:drug effects*; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects / Q000473:pathology*; D008422:Materials Testing; D015162:Micronucleus Tests; D008982:Molybdenum / Q000737:chemistry; D020959:Polyethylene / Q000737:chemistry*; D019736:Prostheses and Implants / Q000009:adverse effects*; D013052:Spectrometry, X-Ray Emission; D014025:Titanium / Q000009:adverse effects*
chemical_list: D000497:Alloys; D001672:Biocompatible Materials; D002857:Chromium; C031462:titanium alloy (TiAl6V4); D003035:Cobalt; D008982:Molybdenum; D020959:Polyethylene; D014025:Titanium
keywords: Cytogenotoxicity; Fractal analysis; Human lymphocyte; Joint replacement; Multifractal analysis; Scanning electron microscope