Orthopedic implants

Implants for controlled release of drugs (nonbiodegradable) Implantable biosensor-drug delivery system Microfiuidics device for drug delivery Controlled-release microchip Implants that could benefit from local drug release Vascular stents coronary, carotid, and peripheral vascular Ocular implants Dental implants Orthopedic implants... 

Orthopedics Today. 1999. Guide to polyethylene in joint implants. Orthopedics Today, Slack, Inc., Oct-Nov. 

The purpose of this document is to list the data needed for orthopedic devices containing UHMWPE. These data should be included in premarket notifications (510k), Investigational Device Exemptions (IDE) applications. Premarket Approval (PMA) applications, reclassification petitions, and master files to aid FDA in determining the substantial equivalence and/or safety and effectiveness of UHMWPE in implantable orthopedic devices. In this document UHMWPE is referred to as polyethylene (PE). 

Katzer A, et al. Two-year results after exchange shoulder arthroplasty using inverse implants. Orthopedics 2004 27(ll) 1165-7. 

The next advance in total hip arthroplasty came with the development of various porous surface treatments which allow bone tissue to grow into the metal porous coating on the femoral stem of the hip implant and on the acetabular component of the total joint replacement. These developments arose because of patients who were not able to tolerate cemented implants because of allergies to the cement, methylmethacrylate. More youthflil patients are better served by a press-fit implant as well. Figure 12 shows the difference between textured and beaded surface-treated orthopedic prostheses. 

Cobalt—Chromium Alloys. Co—Cr and Ni—Cr alloys are used predominately for the casting of removable partial dentures fixed partial dentures (bridges), crowns, and inlays are also cast. Because of high hardness, corrosion resistance, and wear resistance cobalt-chromium alloys are used for bite adjustments and as serrated inserts in plastic teeth used in fliU dentures. These alloys are well tolerated by the body and also are used for dental implants and orthopedic implant alloys. 

Requirements. Requirements for dental implant materials are the same as those for orthopedic uses. The first requirement is that the material used ia the implant must be biocompatible and not cause any adverse reaction ia the body. The material must be able to withstand the environment of the body, and not degrade and be unable to perform the iatended function. 

S. epidermidis is implicated in many medical implant infections. Mechanical heart valves, shunts, catheters and orthopedic devices are examples of implanted devices... 

Initial tests in the rat revealed a high degree of tissue compatibility of Dat-Tyr-Hex derived polymers. More detailed tests are now in progress. In addition, tyrosine derived polymers are currently being evaluated in the formulation of an intracranial controlled release device for the release of dopamine, in the design of an intraarterial stent (to prevent the restenosis of coronary arteries after balloon angioplasty), and in the development of orthopedic implants. The use of tyrosine derived polymers in these applications will provide additional data on the biocompatibility of these polymers. 

Despite the evidence for the cytotoxicity of CNTs, there are an increasing number of published studies that support the potential development of CNT-based biomaterials for tissue regeneration (e.g., neuronal substrates [143] and orthopedic materials [154—156]), cancer treatment [157], and drug/vaccine delivery systems [158, 159]. Most of these applications will involve the implantation and/or administration of such materials into patients as for any therapeutic or diagnostic agent used, the toxic potential of the CNTs must be evaluated in relation to their potential benefits [160]. For this reason, detailed investigations of the interactions between CNTs/CNT-based implants and various cell types have been carried out [154, 155, 161]. A comprehensive description of such results, however, is beyond the scope of this chapter. Extensive reviews on the biocompatibility of implantable CNT composite materials [21, 143, 162] and of CNT drug-delivery systems [162] are available. 

The HAp-agarose hybrid nanomaterial prepared by the electrophoresis approach was also tested for orthopedic surgery implantation in rabbit bone. Figure 6.11 shows... 

Thomas J. Webster, Nanophase Ceramics The Future Orthopedic and Dental Implant Material Yu-Ming Lin, Mildred S. Dresselhaus, and Jackie Y. Ying, Fabrication, Structure, and Transport Properties if Nanowires... 

Toxicity of products released by three alloys for orthopedic implants 185... 

H. Schmotzer, Method for producing implant parts from highly cross-linked uhmwpe and implant parts for human medicine, US Patent 7 364 685, assigned to Plus Orthopedics AG (Rotkreuz, CH), April 29, 2008. 

Using the cage implant system, Kim et al. successfully polymerized a phospholipid on to a solid substrate and found reduced adsorption of proteins such as albumin, fibrinogen, and IgG and also reduced macrophage adhesion.80 There has also been widespread interest in the use of PC coats for orthopedic joint implants as well as other biomedical applications.81 3... 

Nablo BJ, Rothrock AR, Schoenfisch MH. Nitric oxide-releasing sol-gels as antibacterial coatings for orthopedic implants. Biomaterials 2005, 26, 917-924. 

NANOPHASE CERAMICS THE FUTURE ORTHOPEDIC AND DENTAL IMPLANT MATERIAL... 

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