Nanotechnology being used to improve biocompatibility of human prosthetics and implants

As populations of the world age the current trend is that people are not slowing down in their later years. The desire for increased activity among the elderly also means increased demands on medical researchers to come up with better ways to keep them active. In the fields of implants and prosthetics calcium phosphate (CP) coatings on titanium alloy implants are proving their worth in orthopaedic and dental applications.

The most promising form of CP are hydroxyapatite (Ca10(PO4)6(OH)2, HA) coatings used to promote rapid bone remodelling on the titanium alloy implants. It is well known that the microstructure of these coatings significantly influences their mechanical properties and biocompatibility. Understanding the effect of nanostructures within a biocompatible coating could contribute greatly towards improving the effectiveness of these coatings.

In this study by Singaporean researchers, K.A. Khor, H. Li and P. Cheang, from Nanyang Technological University, the nanostructures and in vitro osteoblast behavior of individual CP splats were characterized. The splats were deposited using both plasma spraying and high velocity oxy-fuel (HVOF) onto polished Ti-6Al-4V substrates.

The results showed that the nanostructured HA splats are capable of enhancing the attachment and proliferation of the osteoblast cells. The study also revealed that the dissolution of the Ca/P-rich phases into the culture medium might promote the proliferation/differentiation of the osteoblast cells.