Morphological and Mechanical Biomimetic Bone Structures.

Area of Science:

• Biomaterials Science
• Orthopedic Engineering
• Materials Science

Background:

• Cortical bone exhibits complex 3D compositional and morphological distributions essential for mechanical function.
• Current methods lack the ability to translate X-ray computed tomography (XCT) data into physical outputs with comparable mechanical properties.
• Bridging this gap is crucial for developing advanced anatomical models and functional implants.

Purpose of the Study:

• To develop a workflow for creating 3D printed cortical bone models from high-contrast XCT data.
• To manufacture physical models that mimic the mechanical properties of native bone.
• To explore the relationship between bone remodeling, osteon density, and mechanical performance in 3D printed constructs.

Main Methods:

• Utilized high-contrast X-ray computed tomography (XCT) to generate detailed virtual models of cortical bone.
• Employed multi-material 3D printing to fabricate physical structures based on virtual bone designs with varying secondary osteon densities.
• Applied Hashin-Shtrikman bounds for predicting the elastic modulus of the composite 3D printed materials.

Main Results:

• Successfully created 3D printed composite structures representing cortical bone with diverse secondary osteon densities.
• Demonstrated variability in the mechanical properties of the printed structures through material selection and composition.
• Validated the predictive capability of the Hashin-Shtrikman approach for elastic modulus in these complex composites.

Conclusions:

• The presented workflow enables the creation of 3D printed anatomical models with functional mechanical properties derived from XCT data.
• This approach holds significant promise for generating improved anatomical models and next-generation mechano-mimetic implants.
• The ability to replicate compositional complexity in 3D printed bone structures opens new avenues in orthopedic research and development.