One of the problems with cow bone hydroxyapatite is that it lacks strength. In this video, Dougal Laird, a University of Waikato PhD student, outlines his bioceramic research project, which involves infiltrating the sintered cow bone with certain organic materials in the hope that the strength of the implant can be improved. Dougal’s PhD supervisor is University of Waikato’s Dr Michael Mucalo, and the research is being conducted in association with Dr George Dias from the Department of Anatomy and Structural Biology, University of Otago.
Dr George Dias
My role is to take sintered bone that Dr Michael Mucalo and others have developed and reinforce it with an organic matrix or material, infiltrate it into the sintered bone so that, when it is used as a bone replacement implant, it has greater mechanical strength than it otherwise would have if it was just sintered bone.
Sintered bone is generally only suitable for non-loadbearing situations, so if you put it in the body, for example, and it got a knock perhaps, it would become damaged and the body wouldn't heal so well. So if we can infiltrate some other material into that sintered bone to make it stronger, then perhaps when we implant it, it may maintain its strength and heal better.
When you develop a material that you want to implant in a living organism, you generally go through a series of steps or tests to assess it and make sure that, when you implant it in a person, for example, that it is not rejected, it doesn't cause pain, it doesn't cause infection or anything like that, so you go through these biocompatibility steps.
My supervisor, Dr Michael Mucalo, has a connection in Otago with Dr George Dias, and he is a surgeon down there, and when it came to a stage where we might want to do some biocompatibility testing, then we would go down to Otago. We have done a series of mechanical tests on the materials to show that they are stronger with the infiltrate than the starting material.