Page 30 - eBook_Proceedings of the International Conference on Digital Manufacturing V1

Proceedings of the International Conference on Digital Manufacturing –
Volume 1

collagen synthesis, alkaline phosphatase (ALP) activity, and
osteogenic gene expression (Liu, Dan, Lu & Pan, 2018).
Therefore, in future scaffold designs, careful consideration of
geometry could help modulate local pH environments, balancing
scaffold degradation with optimal bone regeneration responses.

However, excessive pH drops or accumulation of acidic
byproducts may impair osteogenic differentiation or trigger
inflammatory responses (Zhang et al., 2025). This highlights the
importance of balancing scaffold degradation kinetics with
cellular compatibility. Scaffold geometries should be designed to
avoid enclosed regions where degradation byproducts
accumulate, or otherwise be combined with buffering agents such
as calcium phosphates to regulate pH (Zhang et al., 2025).

In summary, incorporating geometry-driven design
considerations into scaffold fabrication allows for enhanced
control over not only mechanical strength and degradation rate,
but also the local biological environment. These insights support
a tailored approach in scaffold design for bone repair, particularly
in critical-size defects, where geometric optimisation can be a
strategic tool to promote effective healing outcomes.

CONCLUSION

This study examined the degradation behaviour of 3D-printed
PLA samples with different geometries in SBF over 28 days. The
results confirmed the slow hydrolytic degradation of PLA and
demonstrated that sample geometry influences both degradation
rate and local pH variation. Higher surface-area-to-volume ratios
accelerated mass loss, while confined geometries induced greater
local pH shifts. These findings emphasise that scaffold geometry
can be strategically designed to modulate degradation behaviour
and the biochemical environment, providing valuable insights for
future bone scaffold development. Future work should focus on
long-term degradation studies under dynamic and physiological
conditions, the incorporation of bioactive materials to enhance

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