生物材料与生物相容性 下载本文

Biomaterials – “Famous Successes”

In many instances, these traditional biomaterials have stood the test of time very well

Cobalt-Chrome and Ti alloys used in orthopedics/ arthroplasty Medical grade stainless steel

Various biodegradable sutures, pins etc Dacron fibre large bore vascular grafts UHMWPE wear liners on hip/ knee prostheses (when done properly!) – UHMWPE still the best Silicone elastomer – great biomaterial used in the right situation

Hard grades of polyether-based polyurethanes

In many cases, however, traditional implants (eg total artificial hips) have a maximum lifetime of approximately 15 years. This is a problem, given our “ageing population”.

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Late 90s – New biomaterials generation

– Large R&D funding injection – Opportunities for improved formulations

– Materials engineered from ground up

– Material-physiological interface studied more extensively – Much tighter control of

manufacture (GLP/ GMP protocols necessary)

– Longer lead times

– More expensive devices

– “Tissue Engineering” field is born and continues to define itself

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Biomaterials Today – accepted themes

– Protein adsorption

– Biospecific biomaterials – Nonfouling materials

– Healing and the foreign body reaction

– Controlled release – Tissue engineering – Regenerative medicine – “nanobiotechnology” – Biomimetics

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New Millennium – Exciting Possibilities!

– Empirical biomaterials science is being replaced by precision design and engineering

– Growing understanding at the cellular and molecular level of “Biocompatibility”

– Biomimetics – mimicing the brilliance and elegance of nature (spider silk, sea urchin spines, bone, coral fish teeth etc) – Nanotechnology, nanostructured biomaterials, “bottom up self assembly”, nanomaterials used for gene delivery etc – “Hybrid” artificial organs – synthetic biomaterials in combination with cells and regenerated natural tissue >> TE – “Intelligent materials”, shape memory, shrink, swell in response to environment

– Teamwork between many disciplines – no boundaries

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