Tricalcium phosphate-based biocomposites for mandibular bone regeneration--A histological study in sheep

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Oral and Maxillofacial Surgery

Background:

• Critical-sized bone defects pose challenges in craniofacial reconstruction.
• Absorbable biocomposites offer potential for bone defect repair.
• Osteopromotive agents are crucial for enhancing bone regeneration within scaffolds.

Purpose of the Study:

• To evaluate the efficacy of three absorbable biocomposites for critical-sized mandibular bone defect repair in sheep.
• To compare the osteopromotive potential of autologous bone marrow, coagulation factor XIII, and whole blood within a polylactide-tricalcium phosphate scaffold.

Main Methods:

• Three-dimensional polylactide scaffolds containing tricalcium phosphate (chronOS) were prepared.
• Scaffolds were augmented with autologous bone marrow (chOS/BoneMarrow), coagulation factor XIII (chOS/FactorXIII), or venous whole blood (chOS/Blood).
• Implantation into critical-sized mandibular defects in 18 adult sheep, followed by histological assessment after 12 weeks.

Main Results:

• chOS/BoneMarrow demonstrated significantly higher new bone formation across all assessed regions (transitional zone, center, periphery).
• The chOS/BoneMarrow group maintained scaffold structural integrity.
• chOS/FactorXIII and chOS/Blood groups exhibited less bone formation and significant scaffold deformation.

Conclusions:

• Autologous bone marrow is a highly effective osteopromotive agent for enhancing bone regeneration within polylactide-tricalcium phosphate scaffolds.
• Coagulation factor XIII did not show a significant bone-promoting effect compared to whole blood in this experimental model.
• The findings support the use of autologous bone marrow in biocomposite strategies for mandibular bone defect reconstruction.