Janus fibre/sponge composite combined with IOPNs promotes haemostasis and efficient reconstruction in oral guided bone regeneration

Placing a barrier membrane between an alveolar bone wound and gingival soft tissue is a common and effective method to prevent fibroblast invasion and promote new bone formation. However, the combined use of a barrier membrane with bone-forming substitutes remains a challenge for dentists during surgery. Thus, a Janus fibre/sponge composite combining iron oxide nanoparticles (IONPs, y-Fe2O3) was fabricated to prevent epithelial invasion and promote alveolar reconstruction. In the scaffold, a poly (lactic-co-glycolic acid)/polycaprolactone (PP) electrospun layer was covalently bound with a chitosan sponge containing y-Fe2O3 by polydopamine. The resilient chitosan sponge can easily adhere to the wound surface and encompass haemostatic capability by swelling and forming blood clots to block bleed-ing. The introduction of IONPs promoted the osteogenesis of rBMSCs, as shown by ALP analysis and cyto-kine assay. The PP layer maintained its structure integrity and prevented epithelial cells from invading into blood clots or fibroblasts from penetrating through the critical pore size. Assessment with a rat model having one-sided calvarial bone injury further confirmed the effectiveness of Janus scaffolds in facilitating the bone regeneration in the postoperative areas. (C) 2022 The Authors. Published by Elsevier Ltd.