Background: Clinical studies have revealed that patients with type 2 diabetes mellitus (DM) have higher implant and bone grafting failure rates than the general population, likely owing to inferior bone healing. The authors sought to investigate whether adipose-derived stem cells (ASCs) combined with inorganic bovine bone improves bone repair in calvarial vertical critical-sized defects (CSDs) in rats with type 2 DM.
Methods: Bovine bone alone or seeded with 3 × 10(5), 3 × 10(6), or 3 × 10(7) ASCs/graft was randomly transplanted into calvarial CSDs in rats with DM induced by a high-fat diet with low-dose streptozotocin. Specimens were assayed using microcomputed tomography and histomorphometry at 4 and 8 weeks postimplantation.
Results: The histologic results showed an increase in new bone formation in the experimental groups compared with the control group. Both bone volume/total volume and trabecular thickness of newly formed bone within CSDs were the highest, and trabecular spacing was the lowest, in the 3 × 10(6) group at 8 weeks for the most favorable outcome. The results showed that the amount of new bone was greatest in the 3 × 10(6) group by 8 weeks.
Conclusions: ASCs enhanced vertical bone regeneration in calvarial defects in rats with type 2 DM, when used in association with bovine bone scaffolds. The findings suggest that a combination of ASCs and bovine bone scaffolds could improve bone quantity in vertical bone defects.