BIOLOGICAL IMPLICATIONS OF POLYMERIC SCAFFOLDS FOR BONE TISSUE ENGINEERING DEVELOPED VIA SOLID FREEFORM FABRICATION - Intelligent Scaffolds for Tissue Engineering and Regenerative Medicine - page 502

25.6 Conclusions
Osteoinduction and osteoconduction are greatly influenced by scaf-
fold architecture. Because of this clinical bone tissue engineering
scaffolds require that scaffolds be made with properties to enhance
bone formation and that these scaffolds be reproducible. SLA, 3DP,
SLS, and FDM all represent promising methods to achieve this. SLA
has been shown to generate scaffolds with the highest porosity and
lowest pore size, but the requirement of a liquid photopolymeriz-
able polymer greatly restricts material choice. Three-dimensional
printing may have utility in some aspects of bone tissue engineer-
ing, but porosities over 50% are di cult to attain and the pore size
isalsolimited.SLSisalsounabletoachieveporositiesover50%and
is very limited in the use of polymeric scaffolds. FDM is able to be
used to fabricate scaffolds with high porosities, but is only able to
beusedwithalimitedamountofmaterials.Manufacturingmethods
thatareunabletoachievescaffoldarchitecturesrequiredofbonetis-
sue engineering may be better utilizedin an indirect approach, with
a secondary method to achieve the necessary pore size and poros-
ity. These approaches have the benefit of creating a scaffold with a
controlled macroarchitecture, while still achieving high-resolution
microarchitectures, but they add an extra manufacturing step and
still leave variation in scaffold design. Cell-based studies using var-
ious SFF techniques have been completed, but more work must be
completed to fully understand the biological implications of these
scaffolds. As the optimal bone tissue engineering scaffold has not
yetbeenfound,additionalresearchneedstobedonetoutilizethese
promisingSFFtechniquesinthemanufacturingofasuccessfulbone
tissue engineeringscaffold.
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