Historically the function of biomaterials was to
replace diseased or damaged tissues. First generation biomaterials
were selected to be as bio-inert as possible and
thereby minimize formation of scar tissue at the interface
with host tissues. Bioactive glasseswere discovered in
1969 and provided for the first time an alternative; strong,
stable interfacial bonding of an implant with host tissues.
In the 1980’s it was discovered that bioactive glasses could
be used in particulae form to stimulate osteogenesiswhich
thereby led to the concept of regeneration of tissues. This
article summarizes the four eras of development of bioactive
glasses that have led from concept of bioactivity to
widespread clinical and commercial use, with emphasis
on the first composition, 45S5 Bioglassr. The four eras
are; A) Era of Discovery, B) Era of Clinical Application,
C) Era of Tissue Regeneration, and D) Era of Innovation.
Key scientific and technological questions answered for
the first three eras are presented. Questions still to be answered
for the fourth era are included to stimulate innovation
in the field.