Bioactive composite membranes: preclinical analysis of PBAT/BAGNb composition to enhance the quality of guided bone regeneration

Bioactive barrier membranes aim to actively contribute to bone formation by promoting cell proliferation, differentiation, and mineral deposition into bone defects. Unlike traditional membranes, they can actively promote bone growth by releasing ions, fostering an optimal environment for GBR. In this study, we aimed to investigate the preclinical behavior of PBAT/BAGNb membranes in a critical-sized defect model in rat calvaria. A flexible and resorbable polyester (poly(butylene adipate-co-terephthalate)) (PBAT) was combined with 30 wt % of niobium-containing bioactive glasses (BAGNb) to produce bioactive composites that were used as membranes for repairing critical-sized calvaria bone defects (Ø5 mm) in an early-stage regeneration preclinical model. The bone formation was evaluated via X-ray microtomography and histological analysis. X-ray microtomography measurements revealed enhanced bone formation in the group treated with the bioactive composite membranes (PBAT/BAGNb) compared to those treated with pure PBAT membranes or left empty (SHAM). The morphometric analysis demonstrated a more densely packed trabecular structure in the newly formed bone of the BAGNb group, indicating tissue maturation within the defects. Histological sections showed minimal signs of inflammation associated with PBAT-based membranes, and mature bone tissue gradually formed with BAGNb in the membranes over time. The preclinical evaluation of PBAT/BAGNb demonstrated enhanced mineral formation and a well-organized trabecular structure, indicating successful outcomes for their use in GBR procedures. A PBAT/BAGNb composite combined flexibility and bioactivity to enhance early bone regeneration, improving mineral formation and a more organized bone structure.