A newer type of operation involves the insertion of a Ascension PyroDisk which is made from a thick pyrocarbon layer encasing a graphite core with a small amount of tungsten. These materials have been shown to be safe when implanted in the body. The PyroDisk is a disk shaped design which has a curved surface designed to fit between the bony surfaces of the trapezium and the metacarpal, reducing pain and allowing for full movement of the joint. It contains a hole in the center through which a strip of tendon can be passed and helps hold the disk in place.