Introduction: Bone repair abnormalities have been associated with diabetes mellitus (DM), including inhibited osteoblastic differentiation, induced osteoblast apoptosis, and compromised angiogenesis. Thus, restoring critical-sized defects is challenging in clinical practice, especially in people with diabetes. Hyperbaric oxygen therapy (HBOT) can be used together with bone grafts to reconstruct these defects.
Objectives: To evaluate the effect of HBOT on the regeneration of critical-sized defects in rats with induced diabetes mellitus.
Materials and methods: Twelve adult male albino rats were divided into two groups of 6 animals each. Animals in both groups were given a single intraperitoneal injection of streptozotocin to induce DM. Critical-sized defects were created in the posterior mandibles and filled with beta-tricalcium phosphate (β-TCP). The study group was subjected to HBOT at (2.4 ATA) for 5 days per week for 90 minutes each. Animals were euthanized one week postoperatively. Bone regeneration was assessed histologically and histomorphometrically. Angiogenesis was evaluated by immunohistochemistry against vascular endothelial progenitor cell marker (CD34), and the microvessel density (MVD) was calculated.
Results: Histological and immunohistochemical results revealed superior bone regeneration and angiogenesis in the study group. These results were further confirmed by the histomorphometrical analysis which showed higher MVD and new bone surface area in the study group compared to the control group.
Conclusions: HBOT enhanced bone regeneration, improved the regenerative effect of β-TCP, and increased angiogenesis in the defects.