Ceramics in orthopedic surgery

Inorganic ceramic compounds have found increasing serviceability as implants in orthopedic surgery and can be classified into general categories using their chemical property characteristics. These characteristics include terms, such as inert, active, and degradable, that normally refer to the ceramics, time-dependent interactions on a relative basis, one-to-another, when implanted in hard and soft tissue sites. The early interest in the high grade (purity and strength) oxide ceramics of aluminum (alumina), titanium [titania], and zirconium (zirconia) was based on information from industrial applications in chemical processing of corrosive solutions. The selection of alumina for high surface area (porous) implants in bone was based partly upon the knowledge that these ceramic materials could maximally resist biodegradation phenomena, while being routinely available at reasonable costs.