A polycaprolactone-β-tricalcium phosphate-heparan sulphate device for cranioplasty

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Orthopedic Surgery

Background:

• Cranioplasty requires graft materials with mechanical strength, bone integration, and aesthetic customization.
• Current cranioplasty graft materials lack a standardized approach.
• Ideal grafts should promote new bone growth and integrate with host bone.

Purpose of the Study:

• To assess the efficacy of 3D-printed polycaprolactone-β-tricalcium phosphate (PCL-TCP) scaffolds modified with heparan sulphate glycosaminoglycan (HS3) for cranioplasty.
• HS3 enhances osteostimulation by increasing affinity for bone morphogenetic protein-2 (BMP-2).
• Evaluate the PCL-TCP/HS3 device in a rat critical-sized calvarial defect model.

Main Methods:

• Created critical-sized calvarial defects in Sprague Dawley rats.
• Randomly assigned defects to four groups: PCL-TCP/Fibrin (control), PCL-TCP/Fibrin-HSft, PCL-TCP/Fibrin-HS3 (5 μg), and PCL-TCP/Fibrin-HS3 (30 μg).
• Evaluated scaffold integration and bone formation at 12 weeks using micro-computed tomography (μCT) and histology.

Main Results:

• PCL-TCP/Fibrin alone or with low HS3/HSft showed limited new bone formation (23.7% BV/TV).
• Scaffolds with 30 μg HS3 demonstrated significantly enhanced bone formation (38.6% BV/TV), 1.6-fold higher than control.
• μCT and histology confirmed superior bone formation and integration with host bone when using sufficient HS3 concentrations.

Conclusions:

• Enhancing biomimicry of PCL-TCP scaffolds with HS3 improves their performance in cranioplasty.
• Heparan sulphate glycosaminoglycan (HS3) with increased BMP-2 affinity promotes bone regeneration.
• This modified scaffold represents a potential treatment for cranial defects.