Biomedical Engineering Reference
In-Depth Information
Ta b l e 3
.
30
Properties of bone, teeth and some biomaterials [72]
Yo u n g ' s
modulus
E
[GPa]
Density
ρ (g/m
3
)
Strength
(MPa)
Material
Hard Tissue
Tooth, bone, human compact bone,
longitudinal direction
Tooth dentin
Tooth enamel
17
0.8
130
18
50
2.1
2.9
138
(compression)
Polymers
Polyethylene (UHMW) 10.94 30
(tension)
Polymethyl methacrylate, PMMA
3 1.1 65 (tension)
PMMA bone cement 21.18 30
(tension)
1
0.94
30 (tension)
3
1.1
65 (tension)
2
1.18
30 (tension)
Metals
316L Stainless steel (wrought)
Co-Cr-Mo (cast)
Co-Ni-Cr-Mo (wrought)
Ti-6Al-4V
200
230
230
110
7.9
8.3
9.2
4.5
1000 (tension)
660 (tension)
1800 (tension)
900 (tension)
Composites
Graphite-epoxy (unidirectional
ibrous, high modulus)
Graphite-epoxy (quasi-isotropic
ibrous)
Dental composite resins (particulate)
215
1.63
1240 (tension)
46
1.55
579 (tension)
10-16
—
170-260
(compression)
Foams
Polymer foams
10
-4
-1 0.002-0.8 0.01-1 (tension)
For the successful achievement of three-dimensional scaffolds,
several characterization criteria are required. They can be divided
into four categories: (i) morphology (e.g., porosity, pore size,
surface area); (ii) mechanical properties (e.g., compressive
and
tensile strength); (iii) bulk properties (e.g., degradation
and
its
relevant mechanical properties);
and
(iv) surface properties (e.g.,
surface energy, chemistry, charge) [63].
Recently, a strong and
bioactive ceramic scaffold consisting
of a porous zirconia body
coated with apatite double layers
(luorapatite (FA) as an inner
layer and hydroxyapatite (HA)
as an outer layer) was successfully
fabricated [66]. The authors investigate the
in vivo
performance of
the engineered
bioceramic scaffolds using a rabbit calvarial defect
model.
In particular, the porosity and pore size of the scaffolds are
varied in order to observe the geometrical effects of the scaffolds
on their bone formation behaviors. The scaffolds supported on
a zirconia framework can be produced with an extremely high
