A medical device is a man made material or objects to alleviate or replace the functions of any body organ/ systems, with out deforming or chemically degenerating or acted upon by body tissues and fluids. In this way medical devices are differentiated from drugs other chemical formulations.
While carrying out the intended activities a medical device becomes a Xenobiotic or foreign body and naturally invokes body response. These responses can be in the form of irritation, inflammation, necrosis, sensitization, cancer etc. and end up in the removal of the medical devices.
Therefore the materials that go into the fabrication have to qualify that they do not invoke body responses. Above we have noted only the general responses. Body responses to various Biomaterials differ depending upon the nature and intended activity of the device as well as the different materials go into the fabrication of each medical devices specifically. Devices that act only on the surface of the skin, devices that penetrate the skin, devices that are going to stay for hours or days such as catheters, dialysis tubes, saline and blood distributing tubes, stents, heart valves etc. gives an idea of different type of medical devices. Dental materials, artificial dentures, contact lens other correctional devices for eyes, artificial hip, bones and knuckles, man made vertebra etc. are in common use at present.
A medical device is “an instrument, apparatus, implement, machine, contrivance, implant, in vitro reagent, or other similar or related article, including a component part, or accessory which is:
- Recognized in the official National Formulary, or the United States Pharmacopoeia, or any supplement to them,
- Intended for use in the diagnosis of disease or other conditions, or in the cure, mitigation, treatment, or prevention of disease, in man or other animals, or
- Intended to affect the structure or any function of the body of man or other animals, and which does not achieve any of its primary intended purposes through chemical action within or on the body of man or other animals and which is not dependent upon being metabolized for the achievement of any of its primary intended purposes.”