Hydrogel-Based 3D Bioprinting for Bone and Cartilage Tissue Engineering.

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Additive Manufacturing

Background:

• Precise control over scaffold micropatterns is crucial for recapitulating native body organs via three-dimensional (3D) bioprinting.
• Hydrogels are critical components of bioinks, but current 3D bioprinting methods expose cells to mechanical and thermal stresses.
• Tuning hydrogel properties is essential to enhance printability, printing quality, and cellular morphology.

Purpose of the Study:

• To review recent advancements in hydrogel-based bioinks for 3D bioprinting.
• To discuss strategies for optimizing hydrogel properties to mitigate printing stresses.
• To explore the simulation of zonal stratification in osteochondral and cartilage tissue engineering.

Main Methods:

• Review of cutting-edge developments in hydrogel-type bioinks.
• Analysis of additive manufacturing strategies impacting scaffold printing quality and cellular morphology.
• Discussion of stabilization techniques, photocurable biopolymers, and cooling substrates.

Main Results:

• Hydrogel rheological, physical, and mechanical properties are key to successful 3D bioprinting.
• Additive manufacturing strategies significantly influence scaffold printing quality and cellular behavior.
• External/internal stabilization, photocurable biopolymers, and cooling substrates can enhance printing fidelity.

Conclusions:

• Optimizing hydrogel bioinks is vital for overcoming 3D bioprinting limitations.
• Understanding the interplay between hydrogel mechanics and printability is crucial for tissue engineering.
• Further research into simulating zonal stratification in complex tissues like osteochondral units is warranted.