Tantalum

Tantalum is a gray heavy metal with an atomic number of 73.  It is a refractory metal, so it has a very high resistance to heat and wear.  Tantalum forms an oxide film that is highly resistant to chemical attack and is unaffected by bodily fluids.  It is also a non-irritating metal, making it suitable for metal implants. Overall biocompatibility of tantalum is excellent.  It is particularly desirable for its superior osseointegration. Osteointegration is the fusion of an implant with bone to form a single cohesive structure. Because of this, tantalum is used as an implant interface of cementless implants.  Tantalum is also used to product artificial trabecular bone with an interconnected pore structure to aid in osteointegration. It has applications as a dental implant and in orthopedics.  Despite the benefits of this material, the very high melting point of tantalum makes it difficult to manufacture into products and contributes to its cost.