Biomaterials artificial hips

The success of hip replacements has been greatly advanced by major development in the biomaterials for orthopedic devices. What aspects of chemistry must be considered in designing an effective artificial hip ... 

Successful applications of materials in medicine have been experienced in the area of joint replacements, particularly artificial hips. As a joint replacement, an artificial hip must provide structural support as well as smooth functioning. Furthermore, the biomaterial used for such an orthopedic application must be inert, have long-term mechanical and biostability, exhibit biocompatibility with nearby tissue, and have comparable mechanical strength to the attached bone to minimize stress. Modem artificial hips are complex devices to ensure these features. 

Let us assume that you or a close relative needs an artificial hip replacement, and that waiting for improved future technologies is not an option. Let us further assume that you have chosen the best surgeon in the particular cotmtry in which you reside, and your chosen surgeon champion will implant any t) e of joint material combination you desire. Having reviewed the biomaterials options that are currently available, as... 

Biomaterials are synthetic or natural materials that are in contact with biological tissues or fluids and may enhance or replace tissues, bones, organs, or body functions (4). They include metals, alloys, glasses, ceramics, natural or syndetic polymers, biomimetics, and composites. Typical biomaterials may be used in artificial skin, tissues, and bones, dental fillings, wire plates and pins for bone repair, artificial hips and joints, implantable drug delivery systems, and other dental, surgical, and medical devices. New and improved biomaterials continue to be sought... 

Tipper JL, Hatton A, Nevelos JE, Ingham E, Doyle C, Streicher R, et al. Alumina-Alumina artificial hip joints. Part II characterisation of the wear debris from in vitro hip joint simulations. Biomaterials 2002 August 23(16) 3441-8. 

In recent times, titanium has become a biomaterial of choice for musculoskeletal implants, such as artificial hip and knee prostheses screws, plates, nails, and intramedullar fixation devices and dental implants." " Titanium and its alloys are recognized within the biomaterials because of their excellent biocompatibility and high chemical inertness of the oxide that covers their surfaces, as well as their mechanical and their osseointegration properties that promote their regular use in biomedical applications." " ... 

The first ever injectable crude biomaterial, that is a dental implant, appeared early in ad 6oo (Fig. 12.1). During those times, Mayan people trimmed seashells into artificial teeth to replace missing teeth (Michael, 2006 Ratner et al., 2004). Early biomaterials also led to problems, including sterilization, toxicity, inflammation, and immunological issues. Since the Mayan s initial use of artificial teeth, biomaterials have evolved to be used in modem artificial hearts, hip and knee pros-theses, artificial kidneys, and breast implants. Materials used in these applications include titanium, silicons, polyurethanes, teflon, polybiodegradable polymers, and most recently bio-nanomaterials (Pearce et al., 2007)... 

The types of medical devices that require biornaterials arc wide ranging across most medical disciplines. " Artificial heart valves, contact lenses, drug delivery implants. urinary catheters, and replacement hip joints are just a few examples that demonstrate where biomaterials can be employed in the body. 

Materials used in biomedical applications (that is, in intimate contact with living organisms) are called biomateriats. We ll see that a biomaterial must meet many requirements to be suitable for such applications as heart valves, artificial tissue, or hip replacement components. 

SASADA, T., TAKAHASHI, M., WATAKABE, M., MABUCHI, K., TSUKAMOTO, Y. and NANBU, M. Frictional behavior of a total hip prosthesis containing artificial articular cartilage, J. Japan. Soc. Biomaterials (in Japanese), 1985, 3, No.3, 151-157. 

The use of metal and metalloid-containing macromolecules is widespread. For example, polysiloxanes are used as biomaterials rather than drugs. Polysiloxanes are widely used as contact lens and in the reconstruction of finger, hip, toe, and wrist joints and in the manufacture of artificial lungs, skin, dialysis imits, orbital floors, tracheal stents, brain membranes, ear frames, and hearts. 

---