SURFACE-TREATMENT OF BIOMATERIALS BY ION-BEAM PROCESSES

Surface treatment of biomaterials is becoming an increasingly popular method of improving device function and biocompatibility without the e xpense and time required to develop new materials. Ion-beam-based proc esses, such as ion implantation and ion-beam-assisted deposition (IBAD ), have proven particularly successful in this area because they offer a wide array of beneficial surface property modifications without adv ersely affecting bulk properties. For instance, orthopedic prostheses are made harder and more wear resistant by ion implanting their articu lating surfaces. Many other devices, such as orthodontic appliances, s urgical instruments and venous catheters, are treated to improve frict ion, fretting resistance and biocompatibility. IBAD is used to apply a ntimicrobial coatings to catheters and other devices, to apply sealant coatings to prevent oxygen or water vapor permeation, and to create m etallized traces on polymers for use in flexible circuitry. This paper reviews the major medical device applications of ion beam-based techn ologies.