Integrating Additive and Traditional Manufacturing for Multiscale Bone Tissue Engineering Scaffolds

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Additive manufacturing (AM) offers precise fabrication of biomimetic scaffolds for bone tissue engineering (BTE).
• AM alone faces limitations in replicating the multiscale hierarchical structures of native bone.
• Traditional fabrication methods can complement AM to overcome these limitations.

Purpose of the Study:

• To systematically review recent advances in constructing heterogeneous scaffolds from a multiscale design perspective.
• To emphasize the integration of AM techniques with conventional methods for bone scaffold fabrication.
• To explore in situ fabrication strategies and pathways for multiscale-integrated scaffolds.

Main Methods:

• Review of major AM techniques (extrusion-based, light-based) integrated with freeze-drying, gas foaming, and electrospinning.
• Focus on emerging in situ fabrication strategies like in situ foaming and mineralization.
• Analysis of approaches for constructing multiscale-integrated scaffolds.

Main Results:

• Integration of AM and traditional methods enables fabrication of scaffolds with controllable macro-, meso-, and microscale architectures.
• In situ strategies allow for spatially resolved and functionally graded scaffold designs.
• Pathways for creating multiscale-integrated scaffolds with enhanced biological performance are identified.

Conclusions:

• Combining AM with traditional techniques is crucial for replicating bone's complex hierarchical structures.
• Emerging in situ methods offer advanced control over scaffold architecture and function.
• This review provides a framework for developing next-generation BTE scaffolds with improved clinical translation potential.