7 research outputs found
A summary of tissue response to the three types of ceramics in different animals.
<p>A summary of tissue response to the three types of ceramics in different animals.</p
Physico-chemical characterization of biphasic calcium phosphate sintered at 1100°C (BCP1100), of biphasic calcium phosphate sintered at 1200°C (BCP1200) and of phase-pure hydroxyapatite sintered at 1200°C (HA1200).
<p>Physico-chemical characterization of biphasic calcium phosphate sintered at 1100°C (BCP1100), of biphasic calcium phosphate sintered at 1200°C (BCP1200) and of phase-pure hydroxyapatite sintered at 1200°C (HA1200).</p
SEM micrographs showing macrostructure (A–C) and surface microstructure (D–F) of BCP1100 (A,D), BCP1200 (B,E) and HA1200 (C,F).
<p>All ceramics were porous with similar macroporous structure (A–C). The surface of the BCP1100 (D) ceramic exhibited smaller grains and a larger number of micropores than the chemically identical BCP1200, that was sintered at 1200°C (E). Grain size and number of micropores in HA1200 were between those of BCP110 and BCP1200 (F), which is in accordance with specific weight measurements in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0107044#pone-0107044-t001" target="_blank">Table 1</a>. Scale bar = 1 mm for A–C and 10 µm for D–F.</p
Histological evaluation of bone formation upon implantation of the three ceramics in dorsal muscles of dogs for 12 weeks.
<p>The highest amount of osteoid and ectopic bone were observed in BCP1100 (A), followed by BCP1200 (B) an HA1200 (C). In all cases, bone was trabecular in appearance, with laminar bone and osteocytes contained in the lacunae, and infiltrated by blood vessels. Decalcified sections, Masson’s trichrome staining, magnification = ×100, scale bar = 200 µm; V→Blood vessel, CT→Connective tissue, M→Material, O→Osteoid tissue, B→Bone.</p
XRD patterns of the three ceramics.
<p>The patterns of BCP1100 and BCP1200 demonstrated biphasic nature of the ceramics consisting of HA and β-TCP. No apparent differences were found as a result of difference in sintering temperature. The pattern of HA1200 was typical of phase-pure hydroxyapatite.</p
Histological evaluation of tissue formation in the three ceramics upon intramuscular implantation in rats, rabbits and dogs.
<p>Representative images showing tissue response to BCP1100 (A, D, G), BCP1200 (B, E, H) and HA1200 (C, F, I) upon implantation in the femoral muscle of rat, dorsal muscle of rabbit and dog for 6 weeks. Decalcified sections, HE Staining, magnification = ×100, scale bar = 200 µm; V→ Blood vessel, CT→Connective tissue, M→Material, O→Osteoid tissue, B→Bone.</p
Delivery of Growth Factors Using a Smart Porous Nanocomposite Scaffold to Repair a Mandibular Bone Defect
Implantation
of a porous scaffold with a large volume into the
body in a convenient and safe manner is still a challenging task in
the repair of bone defects. In this study, we present a porous smart
nanocomposite scaffold with a combination of shape memory function
and controlled delivery of growth factors. The shape memory function
enables the scaffold with a large volume to be deformed into its temporal
architecture with a small volume using hot-compression and can subsequently
recover its original shape upon exposure to body temperature after
it is implanted in the body. The scaffold consists of chemically cross-linked
polyÂ(ε-caprolactone) (c-PCL) and hydroxyapatite nanoparticles.
The highly interconnected pores of the scaffold were obtained using
the sugar leaching method. The shape memory porous scaffold loaded
with bone morphogenetic protein-2 (BMP-2) was also fabricated by coating
the calcium alginate layer and BMP-2 on the surface of the pore wall.
Under both in vitro and in vivo environmental conditions, the porous
scaffold displays good shape memory recovery from the compressed shape
with deformed pores of 33 μm in diameter to recover its porous
shape with original pores of 160 μm in diameter. In vitro cytotoxicity
based on the MTT test revealed that the scaffold exhibited good cytocompatibility.
The in vivo micro-CT and histomorphometry results demonstrated that
the porous scaffold could promote new bone generation in the rabbit
mandibular bone defect. Thus, our results indicated that this shape
memory porous scaffold demonstrated great potential for application
in bone regenerative medicine