Sep 13 2006
Invibio®, a leading provider of biomaterial solutions to the medical device market, today announced the launch of ENDOLIGN™ composite, a new biocompatible carbon fiber-reinforced thermoplastic material for use in implantable load bearing medical device applications requiring blood, bone or tissue contact of more than 30 days. The ENDOLIGN composite and process offer the first non-metallic biomaterial available for medical implants providing the high strength of metals combined with the extensive biocompatibility and imaging compatibility of polymers.
Biocompatibility testing of ENDOLIGN composite confirms that it exceeds the requirements of ISO 10993 standards for long-term implantable medical devices. ENDOLIGN is manufactured to ISO 9001 quality standards by combining high levels of continuous carbon fibers with a PEEK-OPTIMA® polymer matrix in the form of a pre-impregnated tape. This tape can then be molded into rods or other forms. The continuous carbon fibers significantly enhance the mechanical properties of the material, increasing its flexural strength when tested in molded unidirectional rod form, from approximately 150MPa for PEEK-OPTIMA polymer to more than 1000MPa and its stiffness from 3.5GPa to 150GPa.
The mechanical properties of processed ENDOLIGN composite products may be comparable to those of traditionally used metallic materials, such as cobalt chromium alloys, titanium alloys and stainless steel, with the added benefit that ENDOLIGN material offers superior imaging compatibility. Because it is radiolucent, ENDOLIGN enables clear visualization through imaging techniques such as X-ray and Computer Tomography (CT) and being non-metallic, the material is compatible with MRI. Traditional metallic implant materials can generate imaging artifacts and scatter, preventing a comprehensive inspection of the surrounding tissue and bone.
In cases where X-ray visibility is an advantage, ENDOLIGN can be tailored by adding a radiopaque component in different concentrations to vary the level of X-ray contrast.
ENDOLIGN composite can also be repeatedly sterilized using conventional methods including steam, gamma radiation and ethylene oxide processes without adversely affecting its mechanical properties or biocompatibility. Few polymers can be sterilized by all of these methods because of changes that occur within the materials, often leading to embrittlement or hydrolytic degradation.
a“ENDOLIGN composite will enable medical device manufacturers to develop a new generation of implants with better imaging characteristics and improved strength,” said Michael Callahan, president of Invibio. “Because of its outstanding properties, ENDOLIGN is ideally suited for the development of long-term implantable load bearing medical device applications.”
Invibio’s ENDOLIGN composite is currently provided as a pre-preg tape for conventional high performance thermoplastic composite processing by compression molding, autoclave molding, filament winding or pultrusion, or as custom-made pre-formed unidirectionally reinforced rods. Parts can also be fabricated using the novel method of composite flow molding (CFM) by icotec (www.icotec.ch) for which there are CE marked and FDA cleared devices. ENDOLIGN based medical devices also have the potential to be machined from rod stock, plate or other semi-finished product.
ENDOLIGN composite is currently used in the development of load bearing applications including spinal fixation devices like translaminar fixation pins, spinal fusion cages and in trauma devices such as bone fracture plates, screws and intermedullary nails.