Injectable, Hierarchically Degraded Bioactive Scaffold for Bone Regeneration

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Orthopedic Surgery

Background:

• Critical bone defects present significant challenges in bone tissue engineering and regenerative medicine.
• Current methods often struggle with achieving complete and even repair of large bone defects.
• Mimicking the natural creeping substitution process is a key goal for effective bone regeneration.

Purpose of the Study:

• To develop an injectable, hierarchically degradable bioactive scaffold that simulates autologous bone repair.
• To evaluate the scaffold's ability to promote cell proliferation, osteogenic differentiation, and bone formation.
• To assess the scaffold's efficacy in repairing critical bone defects in a preclinical model.

Main Methods:

• Constructed an injectable composite scaffold using hydrogel, decalcified bone matrix (DBM) particles, and bone morphogenetic protein 2.
• Investigated the scaffold's mechanical properties, biocompatibility, and effects on cell signaling pathways.
• Utilized a rat calvarial critical defect model to evaluate in vivo bone regeneration and integration.

Main Results:

• The composite scaffold demonstrated superior mechanical properties and promoted significant cell proliferation and osteogenic differentiation.
• Hierarchical degradation rates of the scaffold components facilitated accelerated tissue ingrowth and woven bone formation.
• In vivo studies showed even and complete repair of critical bone defects, with effective integration of new and host bone.

Conclusions:

• The injectable, hierarchically degradable bioactive scaffold effectively promotes bone regeneration.
• This scaffold represents a promising strategy for achieving even and complete repair of critical bone defects.
• The study successfully simulated the natural creeping substitution process for enhanced bone repair.