KINETICS OF CORTICAL BONE DEMINERALIZATION - CONTROLLED DEMINERALIZATION - A NEW METHOD FOR MODIFYING CORTICAL BONE ALLOGRAFTS

We investigated the kinetics of hydrochloric acid demineralization of human cortical bone with the objective of developing a method of contr olled demineralization for structural bone allografts. It is known tha t the demineralization of cortical bone is a diffusion rate limited pr ocess with a sharp advancing reaction front. The demineralization kine tics of human cortical bone, described as the advance of the reaction front versus immersion time, were determined by measuring extraction o f bone mineral in both planar and cylindrical geometries. Mathematical models based on diffusional mass transfer were developed to predict t his process. The experimental data fit well with the behavior predicte d by the model. The model for planar geometry is applicable to control led demineralization of cortical bone allografts of irregular shapes s uch as cortical struts. The model for cylindrical geometry is appropri ate when curved surfaces are involved such as in diaphyseal bone allog rafts. This method of demineralization has direct application to clini cal modification of cortical bone allografts to potentially enhance th eir osteoinductive properties. (C) 1996 John Wiley & Sons, Inc.