The Slovak research institute in cooperation with university has developed a novel metal composite material for biomedical implants. The composite material fabricated via powder metallurgy comprises bioinert titanium (Ti) matrix and biodegradable component, in particular magnesium (Mg). The metal composite material is suited for implant`s application subjected to and intense mechanical and fatigue loading, particularly a dental implant. The material addresses the shortcomings of existing dental implant concepts based on commercial purity (CP) Ti and Ti6Al4V alloy references i.e.:
- a reduction of the stress-shielding phenomenon, given by a mismatch between Young's moduli (e) of a jaw bone and material of implant; and ii) an insufficient bioactivity. Permanent Ti component material in the composite provides the mechanical properties, required for a function of the implant during a service. Biodegradable Mg component, homogenously dispersed within Ti matrix, reduces E of the composite. Moreover, Mg gradually dilutes at controlled rate from implant`s surface in a contact with a life tissue after implantation. As a result, pores form at prior Mg sites, composite`s E further decreases, the stress-shielding phenomenon reduces, osseointegration process at implant`s interface is promoted and bonding strength increases, eventually. At the same time, owing to unique microstructure of Ti matrix composite material shows good mechanical strength and fatigue endurance comparable to CP Ti.
Ti and Ti alloys are widely applied in biomedicine and in particular for manufacturing of biomedical implants. Ti is biocompatible, non-toxic to humans, inert metal, which is chemically resistant to corrosion in the human body, has high specific strength, is sufficiently ductile and has a low density. The disadvantage of Ti and Ti alloys is their high Young's modulus of elasticity which is several times higher than that of a human bone. Because of this difference, a phenomenon known as stress shielding occurs. As a consequence of the stress shielding phenomenon, the implant transverse significantly higher load compared to the bone, which may lead to atrophy or bone osteoporosis and loosening of the implant.
For materials used for implants manufacturing an appropriate surface treatment is required too, providing good integration with the bone and other biological tissues in order to achieve a firm and lasting connection. Surface treatment of implants leads to a change of topography, morphology and chemical composition of surface and specific surface energy.
The above described disadvantages are substantially eliminated by the unique composite material for implants. Comprising biocompatible Ti or biocompatible Ti alloy and a biodegradable component (in particular Mg). The composite material is manufactured using a cost effective approach, with a sequence of powder metallurgy techniques utilized at low processing temperature. The biodegradable Mg component is after fabrication homogenously dispersed throughout the material’s volume.
The material adopts porous character in vivo, where the biodegradable component is gradually released. Desorption of the biodegradable component contributes to reduction of Young's modulus of the composite material and in the meantime the formed pores increase the contact surface area between the implant and the adjacent tissue, thereby improving the mechanical compatibility and load transfer between the implant and the bone. At the same time dilution of biodegradable component improves osseointegration into implant.
The institute is looking for a partner who would provide investment or other financing to enable the further development of this unique metal composite material.