Bioactive Polymers and Nanobiomaterials Composites for Bone Tissue Engineering - Biomimetics: Advancing Nanobiomaterials and Tissue Engineering - page 92

Biostable
polymers
(PE, PAm,
PEEK,
PMMA)

Biostable
polymer-
nano-
composites

• Mechanical
properties
• Porosity
• Bioactivity

• Mechanical
properties
• Porosity

Synthetic
resorbable
polymers
(PLA, PCL,
PGA, PLGA)

Synthetic
resorbable
polymer-
nano-
composites

• Degradation
• Resorption

• Bioactivity

• Mechanical
properties
• Porosity

Natural
resorbable
polymer-
nano-
composites

Natural
resorbable
polymers (CS,
SA,CA)

• Degradation
• Resorption

• Bioactivity

Figure 5.1 Strategies of polymer nanocomposites preparation to achieve
mechanical, physical and biological properties of the composites for bone tissue
engineering application. Hydroxyapatite (HAp), Tricalcium phosphate (TCP) and
Titanium dioxide (TiO 2 ).

new bone tissue formation, as well as appropriate surface structure for
adhesion and functioning of skeletal cells [15]. The development of 3D
polymer-nanocomposites scaffold is based on the above criteria. Techniques
considered here for scaffold manufacturing polymer nanocomposites are:
solvent casting and particulate leaching, melt molding, gas foaming, elec-
trospinning, microsphere sintering and more advanced rapid prototyping.

5.2.1 Solvent Casting and Particulate Leaching

This is a very simple method for fabricating tissue engineering scaffolds.
With an appropriate thermal treatment, porous structure of scaffolds
can be prepared with specifi c porosity, surface to volume ratio, pore size
and pores interconnectivity. This method involves mixing water-soluble
salt particles (e.g., sodium chloride, sodium citrate) into a polymer-
nanocomposite solution. The mixture is then cast into a mold of desired
shape. After the solvent is removed by evaporation or lyophilization, the
salt particles are leached out to obtain a porous structure [16].

5.2.2 Melt Molding

Melt molding is an alternative method of 3D polymer-nanocomposites
scaffolds fabrication. It has many advantages thanks to modern process-
ing technologies, such as reproducibility, shapeability, homogeneous