The clinical success of an implantable metallic medical device depends not only upon the surgical technique that is used to insert the device, but also on device design, mechanical loading and the response of the surrounding tissues to the metal. Thus, the material composition of the implant is a determining factor for successful implant surgery. Implants fabricated from commercially pure titanium and titanium based alloys have shown impressive clinical results in the fields of cardiovascular, dental, maxillofacial, and orthopaedic surgery. In dentistry, implants serve as a possible treatment for the edentulous patient without many of the disadvantages associated with dentures. A drawback to the implant operation is the recuperation period needed before the patient can load the implant with masticatory forces. In an effort to reduce this period and increase the success rates of implants in the maxilla, this research program proposes to increase cell adhesion and proliferation on the surface of the prosthetic thereby altering the kinetics of bone tissue response to the material and achieving more rapid osseointegration. It is proposed that these objectives can be achieved by modifying the titanium surface chemistry so that selective immobilization of biologically active molecules is possible prior to implantation. To the body, the modified titanium appears as a new material. The outer portion of the surface, i.e. the first 1 nm (1x10[-9] m), dictates what molecules adsorb to the surface and how cells respond to the molecular species adsorbed to titanium. Therefore, the material surface can be engineered to target a specific cell response. The innovative aspect of this study is the selective covalent immobilization of biologically active molecules to titanium. This technology has never been applied to dental materials and has the potential to revolutionize the way implants are currently designed, i.e. biologically engineered implants.
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