Tantalum has been widely used in clinical applications for more than 50 years:
• as a radiographic marker for diagnostic purposes in e.g. orthopaedic surgery, due its high density
• as the material of choice for permanent implantation in bone, as osteomigration prevents migration
• as vascular clips, with the particular advantage that since tantalum is not ferromagnetic it is highly suited to MRI scanning
• in the repair of cranial defects - a United States of America medical material standard exists for tantalum in this application
• as a flexible stent to prevent arterial collapse
• as a stent to treat biliary and arteriovenous (haemodialyzer) fistular stenosis
• in fracture repair
• in dental applications
• in other miscellaneous applications
A number of forms are covered by the standards. ASTM F560 differentiates the product in the following way:
- Tantalum plate for surgery are defined a flat product more than 0.1875 in. (4.7 mm) in thickness.
- Surgical Tantalum sheet are flat products less than 0.1875 in. (4.7 mm) in thickness and more than 6 in. (152.4 mm) wide.
- Tantalum strip is a flat product less than 0.1875 in. (4.7 mm) in thickness less than 6 (152.4 mm) in. wide.
- Tantalum rod for surgery is defined as a material with a diameter between 0.125 to 2.5 in. (3.18 to 63.50 mm) supplied in straight lengths (round, hexagonal, or octagonal cross section)
- ImplantableTantalum wire defined as material up to 0.125" (3.15 mm) in diameter
The ASTM F560 , ISO 13782 and BS 7252-13 specify two acceptable tantalum types: