Influence of Micro-Nanostructured Anatase-Coated SLA Titanium on Macrophage Behavior

The success of titanium dental implants rely on osseointegration, influenced by surface properties and early immune responses. While sandblasted and acid-etched (SLA) titanium surfaces have shown clinical success, macrophage-mediated immune responses at these interfaces remain poorly understood. Anatase nanostructures have been shown to influence macrophage polarization on smooth titanium, but their effects on micro-rough SLA surfaces are not fully explored. This study investigates the immunomodulatory effects of micro-nanostructured anatase coatings on SLA titanium using human monocyte-derived macrophages (MDMs). M0-MDMs, were cultured and polarized to M1 and M2- macrophages on Ti-machined, Ti-SLA, Ti-SLA-anatase, and coverslip control surfaces for 48 h. Macrophage behavior was assessed using CCK-8 assay, confocal microscopy, SEM, ELISA, and qRT-PCR. All surfaces demonstrated excellent cytocompatibility, with similar macrophage viability across all investigated groups. M1 macrophages showed upregulation of CCR7 and TNF-α, while M2 macrophages expressed CD209 and CCL13 across all surfaces. Importantly, Ti-SLA-anatase did not significantly alter M1 or M2 markers, cytokine secretion, or gene expression, and did not exacerbate inflammatory responses. Micro-nanostructured anatase coatings on SLA titanium are immunologically well-tolerated and do not increase inflammation. These findings, combined with previously reported enhanced osteogenic properties, suggest the clinical potential of anatase-coated SLA surfaces.