BIOCOMTIBLE CARBON NANOTUBE/β-Ti COMPOSITE MATERIALS
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Nataliia Stepina and Nicole Grobert
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University of Oxford, Department of Materials, Parks Road, Oxford, OX1 3PH, UK
Nowadays, one of the greatest human health problems is musculoskeletal disorders. It affects hundreds of
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millions of patients all over the world and it is one of the main reasons that cause pain and disability . Also, there
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is a visible effect on societies and economies in general , as it costs society ca. 254 billion dollars . Revision
surgery is necessary after 10-15 years due to the limited lifetime of implants. The release of debris from the
implant into surrounding tissue resulting in bone resorption leads to the loosening of the implant and implant
failure. Unfortunately, revision surgeries are not only very painful for a patient and expensive but also have low
rate of success.
In a recent report on implants it was found that CNTs can foster cell formation but only a comparison of Ti with or
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without CNTs was made, however detailed study of different types and CNT morphologies is very important . It is
well known that properties of carbon nanotubes can greatly vary depending on the production process used to
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synthesize them and on their morphology .
Experiments to date were carried out using ‘activated’ titanium substrates in conjunction with various
hydrocarbons in order to identify CNT growth parameters. SEM studies of the samples produced with toluene
revealed unusual carbon structures rather than CNTs. The structures are ca. 100 nm in diameter and in the
areas of aggregation on the substrate these structures are homogeneous and dense. However, the nucleation of
the particles is not uniform across the entire substrate and will need further investigation. For experiments
conducted with acetylene randomly distributes CNTs could be observed along the substrate. They are short (ca.
200-400 nm) but rather dense which may have a positive effect for improving biocompatibility of Ti. Interestingly
the CNTs appear to possess a bamboo-like structure and probably contain a metal particle at their tips.
Cell work will be performed on the β-Ti /CNT composites to evaluate biocompatibility and suitability of the
composite for osseointagration processes in order to minimise the risk of implant loosening.
References:
1) M. Geetha et al. Progress in Materials Science 54 2009; 397-425
2) N. Grobert, Carbon Nanotubes: Grow or Go, Materials Today 2006, vol.9, no. 10, pp64