In medicine, a prosthesis is an artificial extension that replaces a missing part of the body. Contrast with orthosis that supplements the body. Prostheses are typically used to replace parts lost by injury (traumatic) or missing from birth (congenital), supplement defective parts, allow transsexual men to change their outward physical sex, and achieve secondary sex characteristics for transsexual women, and in movie special effects.

Some types of prosthetics include:

• artificial limbs
• corrective lenses
• cochlear implants
• ocular prosthetics
• facial prosthetics
• somato prosthetics
• surgical prosthetics
• maxillo-facial prosthetics

See also: orthosis