The formation of so-called bioactive bond in which specific compositions of
glasses and glass-ceramics strongly bond with bone, is a complex process highly
influenced by the material surface reactivity when in contact with the biological fluids
and cells. Indeed, non bioactive materials elicit a foreign body reaction and are isolated
by a non adherent fibrous capsule responsible for the failure of many prostheses. It is
clear that understanding the complex mechanisms that form the bioactive bond can help
to design new prostheses and improve the present, increasing their survival rates with
the consequent economic and social benefits. An important role in the bioactive bond
formation is played by biomolecules and cells, which can only be investigated in
complex in vitro cell cultures studies, aided by bioreactors, or in vivo, in animal models.
However, the reason why an implanted material is isolated from the body by a fibrous
capsule or strongly bonded to osseous tissue is its surface reactivity that can be
evaluated under in vitro conditions in artificial solutions with certain blood plasma
characteristics like pH, temperature, inorganic ion concentration, etc. These solutions
were designed to evaluate new candidates to implantable materials and have also led to
great advances in the study of the mechanisms of bioactivity. This chapter presents the
methods used to study the mechanism of formation of bioactive bond.
Keywords: Bioactive glasses, glass ceramics, SBF solution, bioactivity,
hydroxyapatite.
