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A biomaterial, as defined during this handbook, is any synthetic material that’s wont to replace or restore function to a body tissue and is continuously or intermittently in touch with body fluids. This definition is somewhat restrictive, because it excludes materials used for devices such as surgical or dental instruments. Although these instruments are exposed to body fluids, they are doing not replace or augment the function of human tissue. It should be noted, however, that materials for surgical instruments, particularly chrome steel s, are reviewed briefly in, “metallic materials,” during this handbook. Similarly, stainless steels and shape memory alloys used for dental/ endodontic instruments are discussed in, “biomaterials for dental applications.” Also excluded from the aforementioned definition are materials that are used for external prostheses, like artificial limbs or devices like hearing aids [1]. These materials are not exposed to body fluids. Exposure to body fluids usually implies that the biomaterial is placed within the inside of the body, and this places several strict restrictions on materials which will be used as a biomaterial. First and foremost, a biomaterial must be biocompatible-it shouldn’t elicit an adverse response from the body, and the other way around. Additionally, it should be nontoxic and no carcinogenic. These requirements eliminate many engineering materials that are available. Next, the biomaterial should possess adequate physical and mechanical properties to function augmentation or replacement of body tissues. For practical use, a biomaterial should be amenable to being formed or machined into different shapes, have relatively low cost, and be readily available. Lists the varied material requirements that have got to be met for successful total joint replacement [2].

The ideal material or material combination should exhibit the subsequent properties: a biocompatible chemical composition to avoid adverse tissue reactions, excellent resistance to degradation (e.g., corrosion resistance for metals or resistance to biological degradation in polymers), acceptable strength to sustain cyclic loading endured by the joint, a coffee modulus to attenuate bone resorption, high wear resistance to attenuate wear debris generation uses for biomaterials one among the first reasons that biomaterials are used is to physically replace hard or soft tissues that became damaged or destroyed through some pathologic process [3]. Although the tissues and structures of the body perform for an extended period of your time in most of the people, they are doing suffer from a spread of destructive processes, including fracture, infection, and cancer that cause pain, disfigurement, or loss of function. Under these circumstances, it’s going to be possible to get rid of the diseased tissue and replace it with some suitable synthetic material.

Orthopedics

One of the foremost prominent application areas for biomaterials is for orthopedic implant devices. Both osteoarthritis and rheumatoid arthritis affect the structure of freely international. All rights reserved. Handbook of materials for medical devices, handbook of materials for medical devices implants material requirements in orthopedic applications. Source: movable (synovial) joints, such as the hip, knee, shoulder, ankle, and elbow. The pain in such joints, particularly weight-bearing joints like the hip and knee, are often considerable, and therefore the effects on ambulatory function quite devastating. It has been possible to exchange these joints with prostheses since the arrival of anesthesia, antisepsis, and antibiotics, and therefore the relief of pain and restoration of mobility is well known to hundreds of thousands of patients. The use of biomaterials for orthopedic implant devices is one among the main focal points of this handbook. All affect the materials and performance related to orthopedic implants. A variety of metals, polymers, and ceramics are used for such applications [4].

Drug-delivery systems

One of the fastest growing areas for implant applications is for devices for controlled and targeted delivery of medicine. Many attempts are made to include drug reservoirs into implantable devices for a sustained and preferably controlled release. Some of these technologies use new polymeric materials as vehicles for drug delivery. “Polymeric materials,” and 9, “coatings,” in this handbook describe these materials. The lead must be ready to withstand the flexing induced by the cardiac contractions within the warm and corrosive environment within the body. Thus, the materials used must be inert, nontoxic, and sturdy. The lead body must be flexible, noncorrosive, and sturdy [5]. It must also be a good electrical conductor. The early lead body was insulated with polyethylene. Currently, the lead body is insulated with a more resilient material like synthetic rubber tubing or polyurethanes. Polyurethanes are generally stronger than silicone rubbers, which are easily damaged. The strength of polyurethanes enables a thinner cause be utilized in the pacemaker and offers greater lead flexibility. Another advantage of polyurethanes is their very low coefficient of friction when wet. However, metal-ion-induced oxidation may degrade polyurethanes, while silicones aren’t suffering from this mechanism of degradation. The fixation mechanism serves to hold the tip of the lead in place in the heart. Currently, either a nickel-cobalt alloy with a silver core helix or an electrically active platinum-iridium helix could also be wont to anchor the electrode of the cause the surface of the heart. The electrode is found at the tip of the lead. It serves to deliver the electricity from the pacemaker to the guts and knowledge about the natural activity of the guts back to the pacemaker. Electrodes could also be composed of platinum, titanium, stainless steel, silver, or cobalt alloys. Titanium has been used because it forms a no conducting oxide layer at the surface. This surface prevents the exchange of charge carriers across the boundary. Titanium also exhibits a high modulus of elasticity, high resistance to corrosion, and high durability. Electrodes could also be coated with iridium oxide to stop nonconductive layers from forming. The coated electrodes may also provide lower acute and chronic thresholds due to the reduced local inflammation [6].

Acknowledgement

None

Conflict of Interest

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1. DS Metsger, SF Lebowitz (1985) Medical Applications of Ceramics. Med Device Diag Ind 7: 55-63.
2. M Moukwa (1997) . J Met 49:46-50.

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3. SJ Mraz (1991) The Human Body Shop. Mach Des 7: 90-94.
4. K Neailey, RC Pond (1982) . Mater Eng 3: 470-478.

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5. DE Southan (1980) . Met Forum 3: 222-227.
6. RM Waterstrat (1990) . J Met 42: 8-14.

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