The innovative use of specially designed ceramics to repair and reconstruct diseased or damaged parts of the body has improved the quality of life, and in some cases the length of life, for thousands of people. Ceramics used for this purpose are termed “bioceramics” and can be single crystals (sapphire), polycrystalline (alumina or hydroxylapatite), glass (Bioglass®), glass-ceramics (Ceravital® or A/W glassceramic), or composites (stainless-steel fiber-reinforced Bioglass or polyethylene-hydroxylapatite).
Ceramics and glasses have long been used in the health care industry for eye glasses, diagnostic instruments, chemical ware, thermometers, tissue culture flasks, and fiber optics for endoscopy. Insoluble porous glasses have been used as carriers for enzymes, antibodies, and antigens. Ceramics are also widely used in dentistry as restorative materials, gold porcelain crowns, glass-filled ionomer cements, and dentures.
This review describes bioceramics used as implants to repair parts of the body, usually hard tissues such as bones or teeth, but also to replace heart valves. Dozens of ceramic compositions have been tested, but few have achieved human clinical application. Clinical success requires the simultaneous achievement of a stable interface with tissue and a match of the mechanical behavior of the implant with the tissue to be replaced.
The mechanism of tissue attachment depends on the type of tissue response at the implant interface (Table I).