3DP was the first RP technique to be used for biomedical and tissue engineering
purposes.
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In 3DP, the first step is spreading powder onto a platform with a
roller, followed by an inkjet print head printing a two-dimensional pattern onto
the powder layer. After that, the next powder layer is spread and then overlapped
by another layer of inkjet printing until the part is finished. The unused powder is
brushed or blown off afterwards. The process is usually followed by a temperature
treatment to burn the binder off and a final sintering step. Recent research on 3D
printed scaffolds focuses on evaluating the mechanical properties of the scaffolds
both
in vivo
and
in vitro
. Ge et al. proved that the mechanical properties of 3D
printed PLGA scaffolds were close to trabecular bone and that human fetal osteo-
blasts seeded on the scaffolds could proliferate and differentiate normally.
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Serra
et al. fabricated 3D biodegradable PLA/PEG/bioactive glass composite scaffolds
with an interconnected porous structure and improved surface roughness and
hydrophilicity due to the addition of PEG and bioglass.