ABSTRACT
The substance loss from four commercially available Ni-Cr-Mo and four Co-Cr-Mo alloys was examined using a solution of 0.1 mol/L lactic acid and 0.1 mol/L sodium chloride. Dissolved ions were analyzed over a 5-week period using atomic absorption spectroscopy. The results revealed a considerable range of corrosion rates among the Ni-Cr-Mo alloys, with average values after 35 days between 0.54 and 3,261 micrograms/cm2, while the distribution of values for the Co-Cr-Mo alloys was not as wide--between 0.43 and 34.9 micrograms/cm2.
Subject(s)
Chromium Alloys/chemistry , Biocompatible Materials , Corrosion , Ions , Materials Testing , Molybdenum , Regression Analysis , Spectrophotometry, AtomicSubject(s)
Chromium Alloys , Dental Alloys , Gold Alloys , Chemical Phenomena , Chemistry, Physical , Corrosion , Materials Testing , Palladium , SilverABSTRACT
To characterize the galvanic corrosion of supraconstructions consisting of Ni-Cr alloys that come in contact with titanium implants, the resultant substance loss was determined. The measurement of the released substance masses was conducted by analysis of the electrolyte solutions with the aid of atomic absorption spectrometry and by approximate calculation using current density time curves, according to Faraday's law. The results of this study show that both methods allow a clear differentiation of the corrosion behavior of various Ni-Cr alloys that come in contact with titanium.
Subject(s)
Electrogalvanism, Intraoral , Chromium Alloys , Corrosion , TitaniumSubject(s)
Orthodontic Appliances , Saliva/analysis , Trace Elements/analysis , Adolescent , Adult , Child , HumansSubject(s)
Dentures , Gold Alloys , Corrosion , Gold Alloys/analysis , Humans , Mouth Mucosa/analysis , Saliva/physiologySubject(s)
Dental Amalgam , Chemical Phenomena , Chemistry, Physical , Color , Corrosion , Dental Amalgam/analysis , Surface PropertiesSubject(s)
Chromium Alloys , Chemical Phenomena , Chemistry, Physical , Chromium Alloys/analysis , Corrosion , Lactates , Lactic Acid , Sodium Chloride , Surface PropertiesSubject(s)
Chromium Alloys , Beryllium/analysis , Cobalt/analysis , Corrosion , Humans , Nickel/analysis , Saliva/analysisSubject(s)
Carbon , Dental Alloys , Dental Casting Technique/instrumentation , Graphite , Palladium , Dental Porcelain , Metallurgy , Temperature , Time FactorsABSTRACT
Correlation has previously been observed between the incidence of metal hypersensitivity (Ni, Cr, Co) and the incidence of infection after internal fixation of bone fractures. As there is no doubt that exposure to high concentrations of metal can cause allergy, metal levels (Cr, Ni, Mo, Co) were analyzed in implant contact tissues by ASS. Both the absolute concentration of the ions and the Ni:Cr ratio in the tissues adjacent to metal implants is greater in infected cases than in non-infected. Thus infection as a cause of allergy has to be considered. In view of the resulting problems perhaps consideration could be given to the use of a different alloy for metal implants.
Subject(s)
Drug Hypersensitivity/complications , Infections/complications , Stainless Steel/adverse effects , Chromium/analysis , Cobalt/analysis , Corrosion , Fracture Fixation, Internal/adverse effects , Humans , Molybdenum/analysis , Nickel/analysis , Prostheses and Implants/adverse effects , Spectrum Analysis/methods , Time FactorsSubject(s)
Carbon , Dental Alloys , Dental Casting Technique , Chemical Phenomena , Chemistry , Dental Casting Investment , Graphite , MetallurgyABSTRACT
A platelet radioactive antiimmunoglobulin test (PRAT) has recently been introduced. In the present report, a detailed analysis the influence of varying test conditions (i.e. efficiency of iodination of anti-IgG, cell number, degree of sensitization of platelets, times and temperatures of incubation, frequency of washings) on the results of this technique is presented. A standard procedure based on these findings is outlined. It is shown that the PRAT is two to four times more sensitive than platelet complement fixation for the detection of HLA antibodies.
