Single step nanosecond laser structuring for cost effective functional titanium surfaces with topography driven preosteoblast adhesion

Early bone formation around implants depends on both the chemical composition and the micro-, nanoscale architecture of the implant surface. Nanoscale modifications can accelerate osseointegration, and laser processing offers a versatile method of creating such features. In this study, titanium substrates were modified using a single-step nanosecond laser treatment at two energy regimes (1.95 mJ/pulse for P_0.5; 4.00 mJ/pulse for P_0.4). The resulting surfaces were characterized by SEM, EDS, XRD, Raman spectroscopy, ToF-SIMS, contact angle, and topography measurements, with biological assessment performed using a mouse preosteoblast cell line. Analyses revealed various titanium oxo clusters (TiO₃⁻, TiO₂⁻, TiO⁻) and moderate oxidation levels (25-31 at% O). Both laser regimes produced rough, hydrophobic surfaces. Cytotoxicity tests confirmed that the materials were non-toxic, and proliferation assays showed increasing preosteoblast numbers over time, indicating that both surfaces supported cell division. Good adhesion of preosteoblasts was observed on P_0.4 and P_0.5. This work demonstrates that nanosecond laser processing alone can generate micro-, nanostructured titanium implant surfaces with favourable biocompatibility, achieving performance comparable to more complex femtosecond methods while offering a cost-effective and scalable surface engineering strategy.