Kinetics and surface energy approaches to the crystallization of synthetic and biological calcium phosphates

Constant composition methods have been used to investigate the mechanisms of crystal growth and dissolution of synthetic and biological calcium phosphates. Interfacial tensions between water and each of these surfaces were calculated from measured contact angles using surface tension component theory. The data, 4.5 x 10(-3), 8.8 x 10(-3) and 10.4 x 10(-3) J m(-2) for human dentin, human enamel and hydroxyapatite, respectively, compared well with the data calculated from dissolution kinetics experiments and provided information concerning the growth and dissolution mechanisms. The ability of a surface to nucleate other phases is closely related to the magnitude of the interfacial energies.