Page 29 - eBook_Proceedings of the International Conference on Digital Manufacturing V1

Degradation Analysis of 3D Printed PLA in Simulated Body

Therefore, the actual degradation time is expected to be
substantially shorter than the linear prediction.

When considering the known autocatalytic effects, the
projected degradation timeline would realistically fall within the
reported range of ten (10) months to two (2) years for PLA
materials, depending on formulation and environmental
conditions (Shekhar & Mondal, 2024; Khouri et al., 2024). Such
a degradation rate is generally favourable for bone scaffold
applications where gradual resorption is desired to match the pace
of new bone formation (Khouri et al., 2024). Nonetheless, it
should be noted that the current results are based on short-term in
vitro studies under static SBF conditions. Future investigations,
involving long-term degradation profiling and in vivo dynamic
environments, are necessary to validate these projections and to
better understand the interplay between scaffold degradation,
tissue integration and local biochemical responses. Furthermore,
to ensure that the scaffold maintains sufficient mechanical
integrity throughout the degradation window, the optimisation of
scaffold shape and internal architecture also remains essential.

Our study demonstrated that slender geometries, like the
Dogbone, exhibited faster degradation, likely due to their higher
surface-area-to-volume ratios, which enhance hydrolytic
exposure. This characteristic could be advantageous in
applications requiring rapid resorption or facilitating early tissue
ingrowth. Conversely, the Cube structure, which exhibited greater
local pH variation despite lower overall mass loss, suggests that
more confined geometries may create more conducive
microenvironments for mineral deposition or osteoblast activity.

Although these tested geometries do not represent actual bone
scaffold architectures, the observed trends provide valuable
insights for future scaffold design. For instance, controlling
scaffold geometry to adjust surface-area-to-volume ratios may
offer a strategy to fine-tune degradation rates and local
biochemical environments. Bone formation has been reported to
be promoted under relatively alkaline conditions, specifically
when the pH is raised from 7.0 to 7.6, with associated increases in

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