Development of a Bioreactor System for the Cultivation of An Engineered Periodontal Graft

Perfusion culture of oral mucosa substitutes presents a unique challenge due to a wide range of loading conditions on these tissues. In this study, the potential of a novel 3D ex-vivo scaffold derived from the human umbilical vein (HUV) as an oral grafting material cultured in a perfusion bioreactor system that mimics the oral environment was investigated.

HUVs were isolated from umbilical cords using a semi-automated machining technology, and decellularized using two different decellularization methods-surfactant treatment and osmotic lysis. The scaffolds were reseeded with human gingival fibroblasts (hGFs) and cultivated under static and dynamic conditions with varying oxygen tensions. Biological and biomechanical responses of the tissues after 28 days of in vitro maturation were assessed.

Results showed that the dynamic flow conditions improved the cell viability and proliferation, and differentiation of the phenotype of the HUV compared to static culture. The osmotic lysis-treated tissue demonstrated significantly higher initial cell attachment compared to surfactant treatment. The cell proliferation rates achieved with osmotic lysis were significantly higher than the surfactant decellularization. High oxygen tensions proved to aid the biological processes of wound repair.

In conclusion, hGF proliferation within HUV over time was observed indicating active remodeling. The bioreactor configuration adopted in this study evolved HUVs anatomic and functional characteristics that may improve its in vivo performance in periodontal reconstructive and regenerative surgeries.