Prostheses are sometimes used purely for aesthetic reasons. A good example is that used by women who have the misfortune to lose a breast from breast cancer. Prostheses that simulate a person's original body form can often be important in helping the sufferer in his/her self image and confidence.

In fact, almost every lost or missing body part can be cosmetically replaced by a prosthesis if desired, because it's not function you are after, it's looks - something Hollywood has been working on for quite a while.

There are, however, certain body parts which are difficult even to simulate cosmetically. One such part is the human eye. Glass eyes used to be the method of choice, however, these days, eyes made of special polymers preserve the facial sturctures better and tend to get infected much less often than the old glass eyes.

Another body-part that is hard to simulate cosmetically is the tooth. Not only does a tooth have to be replaces for aesthetic purposes, but people still have to use them to eat. Dentures and bridges have been around for a while, but have never been able to emulate the strength and dependability of the original teeth ("Choppers just aren't what they used to be..."). A hot area in Dentistry is the more modern dental implants. A titanium shaft is "screwed" into the jaw, the tissues heal around it, and a false tooth is attached. These tooth-implants are very close to matching the strength of real teeth, and never have to be removed and put in a glass at night.