Mechanical Properties of 3D-Printed Individualized Biodegradable Scaffold for Bone Augmentation

Objectives: The most common approaches for 3D reconstruction of alveolar bone involve methods such as titanium mesh augmentation, the Khoury technique, and distraction osteogenesis. These methods demand highly skilled operators and come with notable drawbacks. An alternative solution could be the utilization of an individualized biodegradable augmentation scaffold (IBAM), which can be digitally designed using the generative design technology and 3D printed. IBAM should mechanically stabilize augmentation material during the stabilization period and withstand forces created by tongue and cheeks (up to 150N) prior its planned degradation.
Methods: The compression strengths of 3D-printed PLA (polylactic acid) specimens were examined on the universal testing apparatus (Inspekt Duo 5kN-M) with the aim to investigate mechanical properties of IBAM. The maximum load for the lateral surface compression strength test was 50N, whereas the maximum load for the upper surface compression testing was 150N. Extended fracture criteria included 4mm stroke of a specimen during the testing. Immersion in the Hanks’ balanced salts solution for 2, 4, 6, 8, 10, 12, 14, and 16 weeks was used to simulate physiological conditions.
Results: The compression strength testing on upper surface showed that specimens immersed in Hanks' balanced salts solution and dry control specimens withstood similar forces ranging from 125 to 150N. Compression strength testing on lateral surface revealed that specimens immersed from 2 to 16 weeks also had similar values when compared to the baseline. Both could endure forces between 46 and 50N.
Conclusions: The compression strength testing demonstrates that IBAM specimens can withstand forces (up to 150N) similar to those produced by the tongue and cheeks in the oral cavity which is crucial for optimal augmentation procedure. Hanks' balanced salts solution did not significantly affect mechanical characteristics of specimens immersed from 2 to 16 weeks (p>0.05).