An artificial organ is a manmade device that is implanted, or integrated into, a human body to replace a natural organ with the purpose of restoring a specific function or a group of related functions so the patient may return to as normal a life as possible. The replaced function need not necessarily have to be related to life support, but often it is.<br />Implied by this definition is the fact that the device must not be continuously connected to a stationary power supply or other stationary resources, such as filters or chemical processing units. (Periodic rapid recharging of batteries, refilling of chemicals, and/or cleaning/replacing of filters would exclude a device from being called an artificial organ.) Thus, a dialysis machine, while a very successful and critically important life support device that completely replaces the functions of a kidney, is not an artificial organ. At this time, an efficient, self-contained artificial kidney has not become available.<br />Reasons to construct and install an artificial organ, an extremely expensive process initially, which may entail many years of ongoing maintenance services not needed by a natural organ, might include:<br />• Life support to prevent imminent death while awaiting a transplant (e.g., artificial heart, kidney).<br />• Considerable improvement of the patient’s ability for self-care and ambulation (e.g., artificial joints, limb).<br />• Improvement of the patient’s ability to interact socially (e.g., cochlear implant, IOL).<br />• Cosmetic restoration after cancer surgery or accident.<br />The use of any artificial organ by humans is almost always preceded by extensive experiments with animals. Initial testing in humans is frequently limited to those either already facing death or who have exhausted every other treatment possibility. (Rarely, testing may be done on healthy volunteers who are scheduled for judicial execution.)<br />Although they are not typically thought of as organs, one might also consider the replacement of bones and joints of the human body or other animals.<br />