Biomedical Engineering Reference
In-Depth Information
In this frame, application of calcium orthophosphates appears to
be logical due to their similarity with the mineral phases of bones
and teeth [62-66]. Calcium orthophosphates are not toxic and do
not cause cell death in the surrounding tissues. However, according
to available literature, the first attempt to use them (it was TCP) as
an artificial material to repair surgically created defects in rabbits
was performed in 1920 [67]. Although this may be the first scientific
study on use of a calcium orthophosphate for bone defects repair,
it remains unclear whether the calcium orthophosphate was a
precipitated or a ceramic material and whether it was in a powder
or granular form. The second clinical report was only published
30 years later [68]. More than 20 years afterwards, the first dental
application of a calcium orthophosphate (erroneously described as
TCP) in surgically created periodontal defects [69] and the use of
dense HA cylinders for immediate tooth root replacement [70] were
reported. According to the available databases, the first paper with
the term “bioceramics” in the abstract was published in 1971 [71],
while with that in the title were published in 1972 [72, 73]. However,
application of the ceramic materials as prostheses had been known
before [74-77]. Further historical details are available in both
Chapter 8 and other publications on the subject [78, 79]. On April
26, 1988, the first international symposium on bioceramics was held
in Kyoto, Japan.
Commercialization of the dental and surgical applications of
calcium orthophosphate (mainly, HA) bioceramics occurred in the
1980s, largely due to the pioneering efforts by Jarcho [80-83] in
the United States, de Groot [84-86] in Europe and Aoki [87-90] in
Japan. Shortly afterwards HA has become a bioceramic of reference
in the field of calcium orthophosphates for biomedical applications.
Preparation and biomedical applications of apatites derived from
sea corals (coralline HA) [91-93] and bovine bone [94] have been
reported at the same time [95].
4.3.2
Chemical Composition and Preparation
Currently, calcium orthophosphate bioceramics can be prepared
from various sources [96-109]. Unfortunately, up to now, all
attempts to synthesize bone replacement materials for clinical
applications featuring the physiological tolerance, biocompatibility
and a long-term stability have had only a relative success; it shows
the superiority and a complexity of the natural structures [110].
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