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 (declared as such by the manufacturer in compliance with 4.1), sum these values and record the sum as the mass fraction percentage of other elements. For an element, that is not a declared alloying element detected in a concentration greater than a mass fraction of 0,1 %, record this value and the name of the element.
6.1.6 Report
6.1.6.1 Test report
A test report shall be prepared. At least the following information shall be included:
a) the name of the dental amalgalm alloy product and its lot number;
b) the name and address of the manufacturer;
c) the International Standard used (i.e. ISO 24234:2021);
d) analytical method used;
e) any irregularities in the test procedure;
f) the mass fraction percentages for those elements that are alloying elements according to Table 1 and declared as such by the manufacturer, as recorded in 6.1.5;
g) if any other element is declared by the manufacturer as an alloying element, report this and its mass fraction percentage as recorded in 6.1.5;
h) each undeclared element found in a concentration greater than a mass fraction of 0,1 % by name and the mass fraction percentage as recorded in 6.1.5;
i) the sum of the mass fraction percentages of undeclared elements present in concentrations greater than a mass fraction of 0,01 % as recorded in 6.1.5;
j) the name and address of the organization responsible for the testing (e.g. test house, university,department of manufacturer);
k) the date of testing.BS ISO 24234 pdf download.