EFFECTS OF SURFACE TOPOLOGY ON TITANIUM RELEASE FROM IMPLANTS INTO RABBIT BONE AFTER 1-YEAR FOLLOW-UP

The material composition and surface structure of dental and orthopaedic implants have important effects on integration of the implants with the surrounding bone, and at the same time, the release of the constituent elements of the implants into the surrounding tissues. It is the aim of this paper to study the degree of release of Ti in relation to the surface roughness of the implants. For this purpose, screw shaped implants were prepared with two different surface topographies; one group was left as-machined, i.e. as machine-turned surface, and the second group was blasted with 25 µm Al₂O₃ particles. The surface topography was measured with a confocal laser scanning profilometer and the surface roughness was characterized using height and spatial descriptive parameters. The as-machined surfaces had an average surface roughness (S_a) of 0.96 µm and the blasted surfaces had an S_a value of 1.16 µm. The implants were inserted into rabbit bone for 1 year. Six samples (three of each type) were prepared for PIXE analysis. The PIXE analysis was done using proton beams from a tandem type accelerator. with an energy of 2 MeV. The results show that at distances of about 2 mm from implant surface, titanium release into hard tissues was found at similar amounts for the as-machined and the blasted implants inserted in the tibia.