Biomedical applications artificial bone

Artificial Soft Biologies. In addition to sutures, polymers are used for a number of biomedical applications, as illustrated in Figure 5.128. Polymers used for hard structural applications such as dentures and bones are presented in this figure, but will be described in the next section. In this section, we will concentrate on polymers for soft biological material applications and will limit the description to mechanical properties as much as possible. 

The major interest in calcium phosphate cements has always been in their potential for biomedical applications. This is because bone contains hydroxyapatite (Ca5(P04)30H), a calcium phosphate mineral. Any material that could be used to bond bone or produce an artificial graft should contain this mineral for compatibility. In fact, much of the research in producing calcium phosphate-based cements or sintered ceramics was motivated by their biomedical applications. We will discuss applications of calcium phosphate cements in detail in Chapter 18. This section describes their materials development. 

Other biomedical applications of polymers include sustained and controlled drug delivery formulations for implantation, transdermal and trans-cornealuses, intrauterine devices, etc. (6, 7). Major developments have been reported recently on the use of biomaterials for skin replacement (8), reconstruction of vocal cords (9), ophthalmic applications such as therapeutic contact lenses, artificial corneas, intraocular lenses, and vitreous implants (10), craniofacial, maxillofacial, and related replacements in reconstructive surgery (I), and neurostimulating and other electrical-stimulating electrodes (I). Orthopedic applications include artificial tendons (II), prostheses, long bone repair, and articular cartilage replacement (I). Finally, dental materials and implants (12,13) are also often considered as biomaterials. 

In this chapter we study the overview of the various naturally and artificially prepared self-assembled nanostructures which are currently very important and in demand in biomedical applications, for example, bone tissues, natural laminated composites present in sea shells, peptide chain arrays and their derivatives and cell membranes are naturally self-assembled materials. And Langmuir—Blodgett films, surfactant-directed nonporous materials, and molecularly directed films, composites, nanombes, nanofibrils, nanowires, spherical vesicles, and template-assisted growth are artificially prepared self-assembled nanostructures. Here we discuss in brief the synthesis of those nanostructures which exist in nature and are prepared artificially to fulfill certain requirements (Figure 2.1). 

However, in the last decade the main application of bacterial cellulose has been in the biomedical materials field [13,46,55-57], Due to its unique nanostructure and properties, microbial cellulose is a nattnal candidate for numerous medical and tissue-engineered apphcations. In fact, much work has already been focused on designing ideal biomedical devices from BNC, such as artificial skin, blood vessels, cornea, urethra, bone, cartilage, porcine knee menisci, and heart valve prosthesis as well as deliveries of drug, hormone and protein [58-62], Figure 2,5 illustrates some of the prospects for the various biomedical applications of BNC-based materials. 

Patents over the last few years dealing with BNC biomedical applications illustrate the scientific advances herein reviewed, such as uses of BNC in composite materials for use in osseous tissue support material, blood vessel prosthesis, artificial skin, cartilage-like biomaterial, implan Czaja support material used for cornea, cartilage connective tissue and ligament repair cement for fixing bones, etc. [54]. 

Teflon was introduced to the public in 1960 when the first Teflon-coated muffin pans and frying pans were sold. Like many new materials, problems were encountered. Bonding to the surfaces was uncertain at first. Eventually the bonding problem was solved. Teflon is now used for many other applications including acting as a biomedical material in artificial corneas, substitute bones for nose, skull, hip, nose, and knees ear parts, heart valves, tendons, sutures, dentures, and artificial tracheas. It has also been used in the nose cones and heat shield for space vehicles and for their fuel tanks. 

Application of ECM in the field of biomedical engineering is well known [64, 85-87]. Stainless steel plates for use in bone surgery and artificial joints (e.g. hip... 

Developments in the u.se of biodegradable polymers in biomedical and surgical applications are reviewed. Applications discussed include tissue engineering, bone fracture fixation devices, resorbable sutures, vascular grafts, temporary barriers for the prevention of postoperative adhesion, artificial skin and systems for controlled drug release. 92 refs. 

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