  Bioactive glasses (BGs) and glass-ceramics (BGCs) have become a diverse
family of materials being applied for treatment of many medical conditions. The
traditional understanding of bioactive glasses and glass-ceramics pins them to
bone-bonding capability without considering the other fields where they excel,
such as soft tissue repair. We attempt to provide an updated definition of BGs
and BGCs by comparing their structure, processing, and properties to those of
other biomaterials. The proposed modern definition allows for consideration of
all applications where the BGs and BGCs are currently used in the clinic and
where the future of these promising biomaterials will grow. The new proposed
definition of a bioactive glass is "a non-equilibrium, non-crystalline material
that has been designed to induce specific biological activity". The proposed
definition of a bioactive glass-ceramic is "an inorganic, non-metallic material
that contains at least one crystalline phase within a glassy matrix and has
been designed to induce specific biological activity." BGs and BGCs can bond to
bone and soft tissues or contribute to their regeneration. They can deliver a
specified concentration of inorganic therapeutic ions, heat for
magnetic-induced hyperthermia or laser-induced phototherapy, radiation for
brachytherapy, and drug delivery to combat pathogens and cancers.
