Evaluation of Atomic Oxygen Textured Pyrolytic Carbon Implants

Pyrolytic carbon has many properties that make it suitable for use in the replacement of small joints [1]. The material has a modulus of elasticity similar to that of bone, good wear and fatigue properties, and excellent biocompatibility. Its biggest disadvantage is inadequate biological fixation. The as-deposited surface of pyrolytic carbon has a pore size of 5-10 μm and a depth of 20 μm. This is much smaller than the ideal pore size for tissue ingrowth [2]. Methods to enhance the fixation of pyrolytic carbon implants have included grit blasting and other surface modifications that did not result in improved fixation [3]. Other methods such as hydroxyapatite coating and porous titanium sleeves demonstrated improved bone attachment but are complicated and expensive procedures. The purpose of this study was to examine the feasibility of texturing the surface of pyrolytic carbon by exposure to direct atomic oxygen in order to enhance biological fixation.