BS ISO 24234:2021 pdf download – Dentistry — Dental amalgam

BS ISO 24234:2021 pdf download – Dentistry — Dental amalgam 4.7 Corrosion resistance of the dental amalgam When conformity to this requirement is determined in accordance with 6.7, the mean value (in newtons) of 10 valid results for corrosion test-pieces shall not be less than 80 % of the mean value (in newtons) of 10 valid results for control test-pieces. 5 Sampling Procure material in packages that have been produced for retail and that are from a single lot. To evaluate a dental amalgam alloy, procure a mass of dental amalgam alloy sufficient to conduct all the testing needed to evaluate the alloy itself and to make the required number of test-pieces, including the maximum number of test-pieces allowed to replace any that are rejected. To make the dental amalgam test-pieces, procure a sufficient number of dental mercury sachets from a single lot that has been produced for retail. These sachets shall comply with the requirements for dental mercury of this document. A minimum of 200 g is advisable. There is waste amalgam with the production of each test-piece and an allowance for this is needed. To evaluate a dental mercury sachet product for conformity to the requirements for dental mercury (see 4.2 and 4.4.1) 30 sachets are required. 6 Test methods 6.1 Chemical composition and purity of the dental amalgam alloy 6.1.1 Principle Chemical analysis of the dental amalgam alloy using an instrumented technique for metallic materials. 6.1.2 Test sample 10 g of dental amalgam alloy powder or dental amalgam alloy tablets, as appropriate. 6.1.3 Apparatus Recognized, instrumented analytical instrument, with sensitivity adequate to determine the composition of the dental amalgam alloy for each of the elements declared by the manufacturer in compliance with 4.1. NOTE Inductively coupled plasma atomic emission spectroscopy (ICP-AES) is an example of a suitable analytical procedure. 6.1.4 Procedure Determine the composition of the dental amalgam alloy for the elements declared by the manufacturer in compliance with 4.1. Other elements may be detected during the analysis, being undeclared or impurities. Determine the concentration of each of these as a mass fraction percentage. 6.1.5 Expression of results Record all alloying elements detected in concentrations greater than a mass fraction of 0,01 % and their mass fraction percentages. For other elements that are detected in concentrations greater than a mass fraction of 0,01 % and below a mass fraction of 0,1 % but are not alloying elements...