Adhesion-Promoting Coating With Osteogenic Pda/Ha Nanoparticles For Osseointegration

This study aimed to develop a composite multifunctional coating (PHG) incorporating gelatin with tissue adhesion-promoting properties and polydopamine/hydroxyapatite (PDA/HA) nanoparticles with osteogenic-promoting properties. Pure titanium foils were treated with alkali heat to create a porous surface. Subsequently, PDA was applied to adhere HA particles, forming a dense nano-HA biofilm. Gelatin was then coated on top to enhance biological airtightness. The surfaces of Ti, P@Ti, PH@Ti, and PHG@Ti were characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and water contact angle measurements. Biological properties were evaluated through cell viability and proliferation assays, cell adhesion and extension tests, immunofluorescent staining, reverse-transcription polymerase chain reaction (RT-PCR), alkaline phosphatase (ALP) activity assay, and calcium deposition assay using rat bone marrow mesenchymal stem cells (BMSCs) and human gingival fibroblasts (HGFs). The PHG coating exhibited good hydrophilic properties and wettability, promoting cell adhesion. HGFs showed increased expression of adhesion-related genes and proteins on the PHG coating. BMSCs demonstrated strong osteogenic differentiation potential and mineralization ability on the PHG coating, as evidenced by increased expression of osteogenic genes, ALP activity, and calcium deposition. The PHG coating, prepared on a porous titanium substrate, can promote both soft tissue sealing and bone formation. This multifunctional coating is expected to be a promising strategy for surface modification of dental implants to improve osseointegration and biocompatibility.