Sunday, April 05, 2009

On biological role of titanium

According to WebElements, “titanium has no biological role”. Having recently acquired a titanium (or rather, Ti6AlV4 alloy) dental implant, I am not convinced. To be a dental implant sounds like a perfectly valid biological role to me. Apparently, osteoblasts like to attach to titanium surface (more precisely, to titanium dioxide, TiO2). However, it is not just the material that matters, it is the shape of the material as well. In the recent paper, in vivo bone binding to TiO2 nanotubes and TiO2 gritblasted surfaces was investigated. The authors have found that

after four weeks of implantation in rabbit tibias, pull-out testing indicated that TiO2 nanotubes significantly improved bone bonding strength by as much as nine-fold compared with TiO2 gritblasted surfaces.
Earlier this year, another study has demonstrated that the fate of human mesenchymal stem cells can be affected solely by the geometry of TiO2 nanotubes:
Small (≈30-nm diameter) nanotubes promoted adhesion without noticeable differentiation, whereas larger (≈70- to 100-nm diameter) nanotubes elicited a dramatic stem cell elongation (≈10-fold increased), which induced cytoskeletal stress and selective differentiation into osteoblast-like cells...

3 comments:

Vegna said...

Just because titanium can be used biologically does not mean it has a normal biological role. When WebElements says that titanium has "no biological role", the implication is that titanium is not essential for any biological processes.

dug said...

In seawater Ti is found at 1 ppb, but in phytoplankton titanium concentrations up to 30 ppm (dry mass) were discovered. While it may or may have no biological role, it is accumulated and probably in conjunction with silicone - for which there has affinities for both ways. (http://www.lenntech.com/periodic/water/titanium/titanium-and-water.htm#ixzz2hvFsYY2B)

dug said...

In seawater Ti is found at 1 ppb, but in phytoplankton titanium concentrations up to 30 ppm (dry mass) were discovered. While it may or may have no biological role, it is accumulated and probably in conjunction with silicone - for which there has affinities for both ways. (http://www.lenntech.com/periodic/water/titanium/titanium-and-water.htm#ixzz2hvFsYY2B)