Biomedical Engineering Reference
In-Depth Information
Table 5.4
Major advantages and disadvantages of the calcium
orthophosphate cements [36, 37, 202]
Advantages
Disadvantages
1. Self-setting ability
in vivo
2. Good injectability that allows
cement implantation by
minimally invasive surgical
techniques, which are less
damageable than the traditional
surgical techniques
3. Good osteoconductivity and
occasional osteoinductivity:
the initial biological properties
of the hardened cements are
similar to those of CDHA or
brushite
4. Can be replaced by newly
formed bone after a period of
time (osteotransductivity)
5. Moldability: the perfect fit to the
implant site, which assures good
bone-material contact, even in
geometrically complex defects.
6. Excellent biocompatibility and
bioactivity
7. No toxicity
8. Low cost
9. Ease
1. Mechanical weakness: limited
use due to potential collapse
of material followed by soft
tissue formation instead of bone
formation (loaded areas). Until
cements with adequate shear
strength are available, most
complex fractures that can be
repaired with cement also will
require metal supports
2. Can be washed out from surgical
defect if excess of blood
3. Lack of macroporosity (especially
interconnected pores), which
prevents fast bone ingrowth
and the cements degrade layer-
by-layer from the outside to the
inside only
4. The
biodegradation of
many formulations is slower
than the growth rate of a newly
forming bone
in vivo
of
preparation
and
handling
10. Setting at body temperature
11. Form chemical bonds to the host
bone
12. Clinically safe materials in their
powder components
13. Can be used to deliver antibiotics,
anti-inflammatory drugs, growth
factors, morphogenic proteins,
etc., at local sites, which are able
to stimulate certain biological
responses *
*
Further studies are necessary.
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