Abstract
The primary events occurring in vivo after implant placement are very important in achieving osseointegration. The objective of this research study was to investigate these primary processes and its variations with different surface treatments of titanium. This may further aid in finding surface characteristics which have a positive effect on osseointegration. Firstly, ion adsorption from a physiological solution and ion and protein adsorption from a simulated in vivo environment to polished, glass bead blasted and alkali etched + heat-treated titanium surfaces were tested with the aid of x-ray photoelectron spectroscopy. Secondly, the adhesion strength of bone cells to the 3 different titanium surfaces in two force directions (normal and tangential to the surface) was assessed with the aid of centrifugal accelerations. The theory here was that ions are adsorbed first to the surfaces, proteins then bind to the ions, and then cells can bind to the RGD sequence in certain proteins. Calcium (Ca) and phosphorus (P) were found to be adsorbed to all titanium surfaces from the physiological solution to varying degrees, however, only trace levels of Ca and P could be detected on all surfaces after exposure to a simulated in vivo environment, instead large amounts of protein were found. Bone cell adhesion strength was found to vary (between <2 x 10-8 N and 8 x 10-8 N) statistically significant (p<0.001 - p<0.05) with surface treatment and force direction. Conclusion: although the surfaces exhibited different responses for individual factors of ion adsorption, protein adsorption or cell adhesion, on balance for all three factors the performance of glass bead blasted titanium surfaces showed the most positive results.