Adhesion-enhancing coating embedded with osteogenesis-promoting PDA/HA nanoparticles for peri-implant soft tissue sealing and osseointegration

Following dental implantation, the characteristic bacterial milieu of the oral cavity may lead to peri-implant inflammation, which can negatively impact osseointegration and cause implant failure. To improve soft tissue sealing around the implant, enhance osseointegration, and improve implant success rates, this paper proposes a composite multifunctional coating (PHG) prepared using gelatin and polydopamine/hydroxyapatite nanoparticles, investigates the effects of this novel coating on cell adhesion, proliferation, antibacterial activity, osteogenic differentiation, and evaluates its immune-related properties. The PHG coating was proved to have satisfactory hydrophilicity and wettability for cell attachment. Furthermore, it improved the expression of adhesion-related genes and proteins in human gingival fibroblasts, indicating its adhesion-promoting effect. Additionally, bone marrow mesenchymal stem cells exhibited strong osteogenic differentiation potential and mineralization on PHG-coated surfaces. Notably, the PHG coating exhibited antibacterial activity against Streptococcus mutans, as well as anti-inflammatory effects, potentially via the regulation of macrophages. Therefore, the proposed PHG coating may promote soft tissue sealing and bone bonding, providing a potential strategy for the surface modification of dental implants.