Bone Regeneration using Silk Hydroxyapatite Hybrid Composite in a Rat Alveolar Defect Model

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Tissue Engineering

Background:

• Autogenous bone limitations necessitate bone graft substitutes.
• Hybrid silk-hydroxyapatite composites mimic natural bone properties.
• Addressing softness and brittleness of individual materials.

Purpose of the Study:

• To evaluate hybrid silk-fibrin-hydroxyapatite scaffolds for bone regeneration.
• To compare new bone formation in different scaffold groups.
• To assess osteoconduction and osteoinduction capabilities.

Main Methods:

• Created critical-sized alveolar defects in Sprague-Dawley rats.
• Utilized three groups: empty defect, silk-fibrin scaffold, and hydroxyapatite-conjugated silk-fibrin scaffold.
• Assessed new bone formation via CT, histology, and Western blot at 4, 8, and 12 weeks.

Main Results:

• Hydroxyapatite-conjugated scaffolds showed significantly higher new bone formation (84.8%) at 12 weeks (p=0.027).
• Histology confirmed osteoblast activity within the scaffold center from week 8.
• Osteocalcin expression was significantly higher in the hybrid scaffold group.

Conclusions:

• Hybrid silk-hydroxyapatite scaffolds promote superior new bone regeneration.
• Demonstrated both osteoconduction and osteoinduction in defect sites.
• No adverse foreign body reactions were observed.