Urinary Bladder Matrix as a Guide Bone Regeneration Barrier Membrane for Inhibiting Cell Invasion and Promoting Bone Formation

Natural resorbable Collagen membranes are widely used in guided bone regeneration (GBR) in oral implantology and prosthodontics. However, the rapid degradation and inadequate mechanical properties raise concerns about potentially compromising the ultimate bone regeneration efficacy. In this study, we developed a novel GBR membrane by coating a urinary bladder matrix (UBM) onto small intestinal submucosa (SIS), a commonly used acellular material, to improve the cell-barrier and bone-regeneration performances. The results showed that the UBM-SIS membrane exhibited superior tensile strength, high compliance, and slower degradation rate compared to a commercial Bio-Gide membrane, thereby enhancing the support and maintenance properties. In vitro studies indicated enhanced osteogenic behavior and higher osteogenic cytokine expression in human bone marrow-derived mesenchymal stromal cells (hBMSCs) cultured with UBM-SIS extract. In canine mandibular defect models, we proved that the UBM layer effectively resisted fibroblast invasion in the early stage, thereby enhancing the bone meal duration and osteoblast growth. Microcomputed tomography analysis revealed the greater quantity and maturity of bone trabeculae using a UBM-SIS membrane, exhibiting enhanced bone formation at 12 weeks and trabecular maturity at 24 weeks. In conclusion, we proposed a modified resorbable GBR membrane that may improve clinical outcomes in prosthodontics.