Bone regeneration of canine skull using bone marrow-derived stromal cells and beta-tricalcium phosphate

The aim of this study was to regenerate high-quality cranial bone using tissue engineering techniques, with subsequent extension to clinical application. Our previous study with a 3-month observation period indicated that a composite scaffold composed primarily of beta-tricalcium phosphate (TCP) had the potential for cranial bone regeneration. In this study, we investigated whether bone marrow derived stromal cells (BSCs) could promote the regeneration of cranial bone as determined after 3 and 6 months.

The pilot study was conducted with 14 adult beagle dogs.

Craniotomy was performed in the same manner used clinically. The bone defect (2 x 2 cm) was created at each canine temporoparietal region. The test animals were divided into three groups. In group I, the bone defect was closed by replacing the original free bone flap without filling the residual gaps. In group II, the gap was filled with a composite scaffold consisting of collagen coated beta-TCP and autologous bone fragments with fibrin glue. In group III, autologous cultured BSCs and the composite scaffold were used to fill the gap. The sites of craniotomy were analyzed with three-dimensional computed tomography and histologic examination 3 and 6 months after the operation.

Bone regeneration was observed in groups II and III, with more extensive formation in group III than in group II. In group I, bone regeneration was not observed.

This study showed that BSCs have the potential to promote cranial bone regeneration and confirmed the efficacy of a composite scaffold made of beta-TCP and autologous bone fragments with fibrin glue.