Mechanical Characterization of Porous Bone-like Scaffolds with Complex Microstructures for Bone Regeneration
Brandon Coburn1, Roozbeh Ross Salary1,2
1Department of Mechanical & Industrial Engineering, Marshall University, Huntington, WV 25755, USA.
Bioengineering (Basel, Switzerland)
|April 26, 2025
Summary
This study evaluated SimuBone scaffolds for bone fracture repair, finding that horizontal deposition yields the highest tensile strength for load-bearing applications. Specific designs offer balanced properties for bone tissue engineering.
Area of Science:
- Biomaterials Engineering
- Regenerative Medicine
- Additive Manufacturing
Background:
- Patient-specific porous osteoconductive scaffolds are crucial for bone regeneration but often lack sufficient mechanical strength and bioactivity.
- Developing biocompatible, biodegradable, and mechanically robust scaffolds is essential for effective bone fracture treatment.
- Current limitations necessitate systematic investigation into scaffold material properties and design optimization.
Purpose of the Study:
- To systematically investigate the mechanical performance of SimuBone, a medical-grade material, across ten distinct triply periodic minimal surface (TPMS) designs.
- To evaluate the tensile, torsional, and compressive properties of parametrically designed TPMS scaffolds fabricated via fused deposition modeling (FDM).
- To identify scaffold designs with optimal mechanical properties for bone regeneration applications.
Main Methods:
- Fabrication of tensile (ASTM D638-14, Design IV) and torsion structures using SimuBone.
- Parametric design of ten TPMS scaffold geometries in Rhinoceros 3D.
- Additive manufacturing via FDM using a microcapillary nozzle (400 µm diameter, 10 mm/s print speed) on a heated build plate (60 °C).
- Mechanical testing including tensile, torsional, and compressive property evaluation.
Main Results:
- SimuBone exhibited a shear modulus of 714.79 ± 11.97 MPa and an average yield strength of 44 ± 1.31 MPa.
- Scaffolds with horizontal material deposition achieved the highest tensile modulus (5404.20 ± 192.30 MPa), suitable for load-bearing applications.
- Scaffold design influenced mechanical behavior, with 'P.W. Hybrid' showing anisotropic properties and 'Neovius' balancing stiffness and porosity.
Conclusions:
- The study systematically characterized the mechanical performance of SimuBone TPMS scaffolds fabricated by FDM.
- Optimized scaffold design and fabrication parameters are critical for achieving desired mechanical properties for bone regeneration.
- The 'Neovius' design presents a promising balance of mechanical integrity and porosity for bone tissue engineering applications.
