Experimental reconstruction of mandibular defects with vascularized iliac bone grafts

Abstract

Purpose: The study evaluated the processes of incorporation and bone remodeling after microsurgical transplantation of iliac crest grafts for mandibular defect reconstruction. Materials and Methods: A defect in the mandibular angle measuring 2 × 4 × 1 cm was reconstructed in six Göttingen minipigs with a microvascularized iliac bone graft based on the circumflex artery. The animals were killed at 14, 28, and 56 days after transplantation and the healing process was histologically examined. Results: Although a constant vascular supply to the graft was restored by the microvascular reanastomosis, necrosis occurred in the major part of the bone marrow. New bone formation from the graft was markedly delayed compred with that from the mandible. Some osteocytes and marrow survived after grafting, but the volume of iliac bone tended to decrease gradually over time. In the 56-day specimens, the border between the graft and the mandible was not clear. Conclusion: These findings indicate that survival of the vascularized iliac bone graft in the minipig is not complete.