Medical implants are being used in every organ of the human body. Current medical implants, such as orthopaedic implants and heart valves, are made of titanium and stainless steel alloys, primarily because they are biocompatible The implant material market has evolved over the years starting from vanadium steel and PTFE to the usage of shape memory alloys and resorbabales. Unfortunately, in some cases these metal alloys may wear out within the lifetime of the patient. At present there is no material which can be categorized as above but continuous research is done to improve the properties of the materials. Metallic Materials, Polymeric Materials and Ceramic Materials are used.Nanocrystalline zirconium oxide (zirconia) is hard, wearresistant, bio-corrosion resistant and bio-compatible. It therefore presents an attractive alternative material for implants. This and other nanoceramics can also be made as strong, light aerogels by sol–gel techniques. Nanocrystalline silicon carbide is another candidate material for artificial heart valves primarily because of its low weight, high strength and inertness.