Session: ASME Undergraduate Student Design Expo

Paper Number: 173256

Mechanics-Guided Osteogenesis: Finite Element and Surface Curvature Analysis With Experimental Validation of Tpms Gyroid Scaffolds 

Triply Periodic Minimal Surface (TPMS) lattice structures mimic the porosity and interconnected architecture of trabecular bone, making them ideal for bone tissue engineering applications. This study investigates the hypothesis that scaffold geometry, specifically strut thickness and surface curvature, correlates with enhanced mechanical properties and osteogenic potential. Gyroid lattices were designed with varying strut thicknesses (0.4 mm, 0.6 mm, 0.8 mm, 1.0 mm, 1.25 mm, and 1.5 mm) and analyzed using predictive modeling techniques.

Static Finite Element Analysis (FEA) and Gaussian curvature mapping were used to identify the most ideal and suboptimal scaffold geometries for experimental validation. FEA predicted that the 0.6 mm scaffold had optimal displacement and stress distribution patterns, with a compressive modulus falling within the range of trabecular bone. In contrast, the 1.5 mm scaffold exhibited excessive rigidity, reduced deformation, and limited strain transfer—features known to hinder osteoinductive signaling. Gaussian curvature analysis revealed that the 0.6 mm scaffold had a more negative mean curvature (−1.39 mm⁻²) compared to the 1.5 mm scaffold (−1.23 mm⁻²), supporting evidence that negative curvature geometries better stimulate mechanosensitive pathways.

For experimental validation, 14 mm × 5 mm cylindrical scaffolds were 3D-printed using polylactic acid (PLA). Scaffolds were imaged using stereo microscopy and scanning electron microscopy (SEM), and porosity was quantified with ImageJ. Mechanical testing was conducted using a 5 kN load cell under the same boundary conditions as the FEA. Experimental modulus values closely matched the FEA results, confirming the predictive validity of the computational modeling. Imaging analysis also showed that porosity decreased as strut thickness increased, supporting the mechanical findings.

To assess biological performance, mesenchymal stem cells (MSCs) were seeded onto the 0.6 mm and 1.5 mm scaffolds and cultured in osteogenic differentiation media for 21 days. Alizarin Red S staining was then performed to detect calcium deposition. Stereo microscopy revealed significantly more mineralization on the 0.6 mm scaffold, with intense staining localized in high-stress regions identified in FEA simulations. These regions also corresponded to areas of higher Gaussian curvature, reinforcing the mechanobiological relevance of scaffold design. The 1.5 mm scaffold showed minimal staining and poor mineralization, consistent with its low curvature and stiff mechanical response.

Overall, the study demonstrates that scaffold designparticularly strut thickness and curvature—plays a critical role in modulating mechanical properties and osteogenic outcomes. The results support the use of TPMS-based scaffolds with optimized curvature and compliant mechanics for bone tissue engineering applications, and offer valuable insights for future scaffold design aimed at enhancing bone regeneration and preclinical translation.

Presenting Author: Jasmine Carpenter Alabama State University

Presenting Author Biography: Jasmine Carpenter is a senior Biomedical Engineering major at Alabama State University, where she conducts research in the Vijayan Laboratory for Polymeric Biomaterials. Her work focuses on the design and evaluation of 3D-printed Voronoi and Triply Periodic Minimal Surface (TPMS) scaffolds for bone tissue engineering. She integrates predictive modeling; including finite element analysis, surface curvature mapping, and pore structure quantification, with experimental approaches such as compression testing, stereomicroscopy, and porosity analysis to validate scaffold performance. Jasmine has presented her research at ABRCMS 2024 and ERN 2025, receiving travel awards for her contributions. Passionate about advancing regenerative medicine, she plans to pursue a Ph.D. in Biomedical Engineering to further explore biomaterials and mechanobiology.

Authors:

Jasmine Carpenter Alabama State University
Pratheesh Kumari Alabama State University