The surgical implant materials received were identified as follows: TEst procedure In the electrochemical technique chosen, cyclic potentiodynamic polarization, a metal specimen working electrode is exposed to the solution in a test cell fitted with a reference electrode saturated calomel and a counter electrode graphite. The potentiostat is connected to these three electrodes, and the potential of the working electrode, with respect to the reference, is scanned through a voltage range from negative to positive, and then reversed to its starting potential. The resulting current between the working and counter electrodes is recorded. This scan is then plotted on a semi-log graph, allowing the resulting curve to be analyzed for key-point voltages and currents. An electrical lead was connected to each specimen.
|Published (Last):||11 January 2006|
|PDF File Size:||3.31 Mb|
|ePub File Size:||4.88 Mb|
|Price:||Free* [*Free Regsitration Required]|
More F During the selection process of a material for use as an implantable device, testing the corrosion resistance of the material is an essential step; however, it does not necessarily provide critical data regarding device performance. The results of this corrosion test conducted in artificial physiological electrolytes can provide useful data for comparison of different device materials, designs, or manufacturing processes. However, note that this test method does not take into account the effects of cells, proteins, and so forth, on the corrosion behavior in vivo.
Scope 1. Examples of device types that may be evaluated by this test method include, but are not limited to, vascular stents, ureteral stents Specification F , filters, support segments of endovascular grafts, cardiac occluders, aneurysm or ligation clips, staples, and so forth.
These small devices should be tested in their entirety. The upper limit on device size is dictated by the electrical current delivery capability of the test apparatus see Section 6. No other units of measurement are included in this standard.
It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
Learn about our Engaged Experts The human body and its immune and inflammatory mechanisms can create an aggressive environment for metallic implants resulting in implant rejection and failure Gilbert, Corrosion, ;73 12 In vitro testing of small implants is typically performed per ASTM Fb to mitigate these risks. While this testing helps determine implant susceptibility to corrosion, it does not take into account the effects of cells, proteins, and other biological effects that implants will experience in vivo. The standard provides a test method for conducting cyclic forward and reverse potentiodynamic polarization measurements on whole devices in their final form and finish. In the sections below, we describe the test methods, apparatus, results and acceptance criteria used in vitro corrosion testing of small implants.