Micro-plasma textured Ti-implant surfaces

Abstract

The surface state of titanium implants modulates bone response and implant anchorage. This evidence brought implant manufacturers to switch from the standard surface refinements and implement new surface treatments for more bone apposition and enhanced interfacial strength measured by removal torque or push-out tests. Anodic plasma-chemical treatment of implant surfaces is a cost-effective process to modify surface topography and chemistry. This technique is used for structuring connected with a coating of implant surfaces. The aim of our investigations, here, is to texture the implant surface in the nanoscale without coating. Ti disks with different mechanical pre-treatment (grinded, glass blasted) were used as substrate. Micro-plasma texturing was carried out in an aqueous electrolyte. By applying a pulsed DC voltage to the specimen, micro-plasma discharge was generated in the thin steam film between immersed specimen and electrolyte. The electrical process parameter current density was varied. The micro-plasma textured Ti surfaces were characterised optically by SEM and electrochemically by CV- (for testing the corrosion parameters), CA- (to give the enlargement of the real surface) and EIS-measurement in range of 100 kHz-100 microHz. We found that the initial structure of the material surface has small or no influence on the results of the micro-plasma treatment. The properties of the thick oxide layer resulting from the plasma process are influenced by electrical process parameters. After removal of the thick oxide layer a fine, micro- and nanoscaled surface structure of the titanium remains.