Barbieri Thesis - BioMedical Materials program (BMM)

Chapter 7 – Polymer mole ecular weight annd
instructive co omposites
Table 3. Perccentage
of coverring
perimeter (% %pt.) and thicknesss
of apatite laye ers onto the surfa ace of the two
materials (ass
evaluated from BSEM images) in their starting conditions, after
two days in SB BF, after 12–
week degradation
in vitro (SPPS)
and after three
months implanntation
in muscle of dogs. For com mpleteness, in
brackets aree
reported the ppercentage
varia ations respect too
the starting conditions c of lay yer thickness
(calculated on
the final averagge
measured values).
Statistical ccomparison
is ex xpressed in terms s of p–values
in the text.
As prepaared
2–days SBF
12–weeks
in vitro
12–weeks
in vivo
ML
– perimeter [% %pt.] 73.9±8.55
86.5±6. 4
67.3±10.5 84.9±5.9
– thickness [m]
MH
11.7±2.88
29.1±6. 2 (+148.8%) 10.2±2.7 (–12. 8%) 32.6±6.2 (+178.3%)
– perimeter [% %pt.] 74.8±7.66
86.3±5. 0
69.6±8.3
85.5±8.3
– thickness [m]
10.4±2.33
22.8±4. 7 (+119.3%) 9.1±3.2 (–12.7 7%) 19.0±4.0 (+83.1%)
Figure 2. SEEM
images showwing
the similarity y between the suurface
of (a) ML and (c) MH granules.
BSEM
images of crross–sections
of the starting surf face of (b) ML aand
(d) MH granules.
Alkali treatment
caused
partial removval
of polymer froom
the surfaces and exposed appatite
particles generating g calcium
phosphate
apatite layerss
(white triangless)
surrounding the
granules of booth
materials. Ho omogeneous core es were seen
in both materrials
(*).
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