This study reports on an original concept of additive manufacturing for the fabrication of
tissue engineered constructs (TEC), offering the possibility of concomitantly manufacturing a
customized scaffold and a bioreactor chamber to any size and shape. As a proof of concept
towards the development of anatomically relevant TECs, this concept was utilized for the
design and fabrication of a highly porous sheep tibia scaffold around which a bioreactor
chamber of similar shape was simultaneously built. The morphology of the bioreactor/scaffold
device was investigated by micro-computed tomography and scanning electron microscopy
confirming the porous architecture of the sheep tibiae as opposed to the non-porous nature of
the bioreactor chamber. Additionally, this study demonstrates that both the shape, as well as
the inner architecture of the device can significantly impact the perfusion of fluid within the
scaffold architecture. Indeed, fluid flow modelling revealed that this was of significant
importance for controlling the nutrition flow pattern within the scaffold and the bioreactor
chamber, avoiding the formation of stagnant flow regions detrimental for in vitro tissue
development. The bioreactor/scaffold device was dynamically seeded with human primary
osteoblasts and cultured under bi-directional perfusion for two and six weeks. Primary human
osteoblasts were observed homogenously distributed throughout the scaffold, and were viable
for the six week culture period. This work demonstrates a novel application for additive
manufacturing in the development of scaffolds and bioreactors. Given the intrinsic flexibility
of the additive manufacturing technology platform developed, more complex culture systems
can be fabricated which would contribute to the advances in customized and patient-specific
tissue engineering strategies for a wide range of applications.
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