Biomedical Engineering Reference
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to rapid, physiological bone ingrowth. The use of active substances or growth
promoters locally released by these mixtures will make possible fast, biological
secondary hardening.
4.4.9 BCP/Fibrin Glue
The association of bioceramics (Tricos®) and fi brin sealants may develop the
clinical applications of composite bone substitutes [106]. As far as the calcium
phosphate granules are concerned, they are not easy to handle. They are limited
to fi lling bone cavities and are not available for bone apposition. In addition, im-
proved performances of bioceramics can be made by adding bioactive factors. In
this context, the adjunction of a binding agent such as fi brin glue facilitates the
stability of the granules at the site of implantation and provides the scaffold effect
of bioceramics with additional osteogenic property. Fibrin-calcium phosphate
composite was obtained by mixing Baxter's fi brinogen, the thrombin components
of fi brin sealant (Tisseel
®
Baxter BioSciences BioSurgery) and TricOs
®
granules.
Macroporous Biphasic Calcium Phosphate TricOs
®
is a mixture of HA/
- TCP in
a 60/40 ratio. Granules of one to two mm in diameter presenting both macro-
porosity (50-55%) and microporosity (30-35%) were used. To enhance the work-
ing time, a low thrombin concentration (four U) was used. The Tisseel/TricOs
volume ratio was one for two. Numerous preclinical studies have been performed
in rabbits and goats, both for biocompatibility and biofonctionality using, for ex-
ample, sinus lift augmentation, and bone fi lling in long bone. Histology, histomor-
phometry and X-ray microtomography have shown the osteogenic properties of
the composite [106,107] (Figure 4.15 ).
β
0.5
mm
Figure 4.15.
Polarized light microscopy of the Tricos granules combined with fi brin glue Tis-
seel in a rabbit femoral epiphysis defect showing large bone ingrowth into the macropores
surrounding the not yet resorbed granules.
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