Investigation of tissue/implant interactions during the first two hours of implantation

The objective of this study was to determine whether detectable differences exist in the initial process of tissue incorporation of implant materials of different original surface energies. Our earlier work focused on materials implanted for days to months; the experiments reported here addressed the initial 2 hours of implantation. Surface-treated metal implants were placed in the fascial plane in the back of New Zealand white rabbits for 5 minutes to 2 hours. Prior to implantation, the metal plates were characterized by infrared spectroscopy, ellipsometry, and contact potential methods; the same analytical techniques, as well as scanning electron microscopy and contact angle measurements were applied to the explanted samples. No significant cellular adhesion was observed within the first 2 hours of implantation. Films rich in lipids and proteins were detected on the implants, however, within 5 minutes. There is good evidence for specific film differentiation as a function of differing initial substratum surface energies.