In vitro evaluation of atmospheric plasma treatment for enhancing the biological response of a laser textured titanium dental implant surface

A standard titanium grit-blasted acid-etched (GBAE) surface, a patterned titanium laser surface (LS) and the same LS treated with atmospheric plasma (Plasma-LS) were characterized morphologically and chemically through Scanning Electron Microscope/Energy Dispersive X-ray analysis. According to the X-ray Photoelectron Spectroscopy C, O, and N were the most abundant contaminants on the three titania surfaces. Based on multi-parametric surface measurements, including the developed interfacial area ratio (Sdr), LS (Sdr = 105.00 +/- 3.00%) and Plasma-LS (Sdr = 50.00 +/- 3.00%) exhibited significantly higher values compared to GBAE (Sdr = 3.05 +/- 0.11%). As for the optical contact angle measurements, Plasma-LS did not show detectable angles, while LS presented greater affinity to both water and diiodomethane compared to GBAE. Plasma-LS displayed the highest total surface energy (73mJ/m2), almost equally distributing the polar (gamma P) and dispersive (gamma D) components, while gamma P/gamma D ratio was close to 1/3 in GBAE and LS. Plasma-LS adsorbed significantly the highest amount of bovine serum albumin. At 24 h, on GBAE, cells spread more and were more circular than on LS and Plasma-LS. Based on the viability assay, Plasma-LS, outperformed significantly GBAE and LS, after 3 and 7 days of culture. Further studies and clinical trials are required to establish the efficacy and safety of this acid-free surface modification for osseointegration.