Ceramics in Biology and Medicine

Abstract

Chapter 35, Ceramics in Biology and MedicineBioceramics are ceramics used for the repair and reconstruction ofhuman body parts. Thereare many applications for bioceramics, currently the most importantis in implants such asalumina hip prostheses. Alumina is classified as an inert bioceramicbecause it has very lowreactivity in the body. However, bioactive materials have the abilityto bond directly with bone.The advantages areEarlier stabilization of the implantLonger functional lifeBioactive ceramics are relatively weak compared with common implantmetals and highstrength ceramics such as alumina and zirconia. As a result they areoften used as coatings,relying on the mechanical strength and toughness of the substrate.An important bioactiveceramic is hydroxyapatite (HA). Natural bone is a composite in whichan assembly of HAparticles is reinforced by organic collagen fibers. Hydroxyapatite-reinforcedpolyethylene compositeshave been developed in an attempt to replicate the mechanical behaviorof bone.A major problem with this topic stems from the realization that youcannot replace boneif you do not understand why bone has such incredible mechanical properties.So if you workin this field you must learn about biology.