Study of micro-arc oxidation-polydopamine-nanoclay (MAO-PDA-NC) composite coating on osteogenesis in cranial defect areas of rats

To investigate the osteogenic potential of a novel composite coating —micro-arc oxidation combined with polydopamine and nanoclay (MAO-PDA-NC)— on titanium substrates, coatings were fabricated via micro-arc oxidation (MAO) and impregnation techniques. Pure titanium (TI) was the control, while MAO-PDA-NC-coated titanium functioned as the experimental specimen. After surface characterization, a 5 mm critical-sized calvarial defect model was established bilaterally in rat skulls. Titanium implants were randomly allocated to the defect sites, either uncoated or coated with MAO-PDA-NC. The regenerative response was assessed through micro-computed tomography, histological analysis, immunohistochemistry, and immunofluorescence. Results demonstrated that MAO-PDA-NC-modified titanium significantly enhanced new bone formation, exhibiting anti-inflammatory and regenerative properties. These characteristics show broad application prospects in the field of implant surface modification.