After studying this chapter you will be able to identify all of the significant applications of biomaterials in those devices that replace the structure and/or function of tissues and organs by the use of medical devices. These may be implanted within the patients, usually for the remainder of their lives, or connected to the patient for some short-term assistance; these applications were summarized at the end of Chapter 1. This discussion covers all of the clinical disciplines. It includes implantable devices that have been in use for decades, and you will be able to understand the reasons for their success, and the reasons for failures where they have occasionally occurred. It also covers the implantable and support systems that have recently been developed and introduced into clinical practice so that you can appreciate where the technology of the twenty-first century is leading us in health care products.

As noted earlier, implantable medical devices were, for many years, the main focus of attention within biomaterials science. The rationale and performance of such devices are discussed in this chapter. Each application and each situation is different and it is not possible to deal with this in an entirely satisfactory systematic manner, but the major headings given in Chapter 1 are covered and dealt with in relation to the clinical discipline that is involved. This includes permanent (or long-term) devices, short-term devices, invasive but removable devices and artificial organs or assist devices that are attached to the body. We will conclude the chapter with an assessment of the overall performance of implantable devices and the lessons learned.