Testing and introduction of new materials - Orthopaedic Biomaterials in Research and Practice - page 382

information for device designers and manufacturing engineers, and,
finally, to verify the performance of materials in manufactured devices.
However, selection of appropriate biologic tests is a much more dif-
ficult and controversial process. There are no Federal regulations that
dictate test selection, but there is an American Society for Testing and
Materials (ASTM) consensus standard, F 748 (F 748-06 [2010]: Standard
Practice for Selecting Generic Biological Test Methods for Materials
and Devices. Volume 13.1, Annual Book of Standards: Medical Devices .
American Society for Testing and Materials, Philadelphia). This guide
considers implant applications in terms of general type of device, the
principal tissue to be contacted, and, if implanted, the period of implan-
tation. For chronically implanted devices intended to contact bone and
tissue, but not blood, the following tests (listed in Table 15.3) are recom-
mended. The overall philosophy of these recommendations is to estab-
lish a reasonable level of confidence concerning the biologic response to
a material or device containing that material when it is introduced into
clinical trials. A standard used throughout Europe is ISO 10993, which
is for evaluating the biocompatibility of a medical device (ISO 10993:
Biological evaluation of medical devices. International Organization for
Standardization, Switzerland). This includes a series of 20 standards,
covering aspects from identification and quantification of degradation
products to a variety of biological tests. In 1995, the FDA issued its own
version of ISO 10993-1 to provide guidance on biocompatibility test-
ing and evaluations. Once the key categories of biological effects for
the biomaterial have been identified, various sources of information can
be used to confirm that each effect has been adequately addressed. For
example, safety data from previous studies using the same material, data
from raw material vendors, and data from prospective studies can all
be used.
Table 15.3 biologic tests suitable for
biomaterials for chronic (>30 days) bone and
soft tissue contact
Cytotoxicity (cell culture)
Short-term intramuscular implantation (animal)
Carcinogenicity (cell culture)
Long-term implantation (animal)
Systemic injection acute toxicity (animal)
Skin irritation or intracutaneous injection (animal)
Genotoxicity (cell culture)
Pyrogen test (animal)
Sensitization test (animal)
Immune response
Source : See F 748-06: Standard Practice for Selecting
Generic Biological Test Methods for Materials
and Devices. Volume 13.1, Annual Book of
Standards: Medical Devices . American Society
for Testing and Materials, Philadelphia.