A Novel Multifunctional Pei@Mgshss-Dap Hydrogel For Periodontal Regeneration

To formulate a novel injectable thermosensitive hydrogel with antibacterial, anti-inflammatory, osteogenic properties to promote periodontal regeneration. Hollow magnesium silicate nanoparticles (MgSHSs) were synthesized via Mg²⁺ etching of mesoporous silica and subsequently surface-modified with PEI. Daphnetin (DAP) was loaded into PEI@MgSHSs via physical mixture, and the resultant nanoparticles were incorporated into a Pluronic F127/β-GP hydrogel to form an injectable composite (iPPMD). Characterization of MgSHSs using TEM, XRD, UV-Vis, and FTIR confirmed successful DAP loading. The stability and DAP release profile of the system were evaluated, and its antibacterial, anti-inflammatory, and osteogenic properties were assessed in vitro. In vivo efficacy was examined in a periodontitis rat model using Micro-CT and WB to evaluate periodontal tissue healing and regeneration. Statistical analysis were performed using one-way ANOVA and Tukey multiple comparison tests. The characteristic peaks in iPPMD polymer confirmed the successful synthesis of PMD, rheological tests showed that iPPMD has good thermosensitive properties (P<0.05). CCK-8 and cytoskeleton assays indicated that iPPMD enhances HGF proliferation under inflammatory conditions, and the decreased IL-6 and IL-1β expression (P<0.05) indicated its anti-inflammatory effect. Live/dead bacterial staining and CFU assays indicated iPPMD inhibits the growth of A.actinomycetemcomitans and P.gingivalis (P<0.05). Micro-CT, HE staining, TRAP staining indicated that iPPMD reduces inflammation-induced bone loss and promotes periodontal tissue regeneration (P<0.05). iPPMD hydrogel possesses excellent antibacterial, anti-inflammatory, osteogenic properties and could stimulate periodontal regeneration in vivo.