Effects of Local Delivery of Vascular Endothelial Growth Factor on Biological Performance of the Composite Biomaterial Used to Accelerate Bridging of Critical-Sized Mandibular Bone Defect in Rabbit Model

This study was aimed to produce a clinically applicable model of composite bone graft capable of treating CSBDs in the mandible with a single surgical procedure. Twelve male white New Zealand rabbits were divided into two groups: control, n=4, consisting of A (untreated) and B (BCP/FS); experimental, n=8, named C (BCP/FS) and D (BCP/FS+VEGF). A circular CSBD (8-mm Ø) was created on both sides of the mandible. Four rabbits were prepared for BCP/FS on one side of the mandible, leaving CSBD on the other side of the mandible untreated. Another set of eight rabbits with CSBDs created on both sides of the mandible was treated with BCP/FS on one side and BCP/FS loaded with 500ng/ml VEGF on the other side. Two rabbits each from the experimental group and one rabbit each from the control group were sacrificed at 14, 30, 45 and 60 days post operatively. All collected samples from CSBDs-site were subjected to micro computed tomography (μCT) and quantitative and semi-quantitative histological examinations. The results showed that the residual composite was significantly lower at 8 weeks in D (BCP/FS loaded with 500ng/ml VEGF) with more new bone formation compared with other groups. Data collected confirmed the applicability of this novel composite matrix for application in bone regeneration in CSBDs.