This workaimedtocomparethecapabilityofStreptococcus oralis to adhere to a novel surface,
double-etched titanium (DAE), in respect to machined and single-etched titanium. The secondary
outcomewastoestablishwhichtopographicalfeaturescouldaffecttheinteractionbetweentheimplant
surface and bacteria. The samples’ superficial features were characterized using scanning electron
microscopy (SEM) and energy dispersive x-ray spectrometry (EDS), and the wetting properties were
tested through sessile methods. The novel surface, the double-etched titanium (DAE), was also
analyzed with atomic force microscopy (AFM). S. oralis was inoculated on discs previously incubated
in saliva, and then the colony-forming units (CFUs), biomass, and cellular viability were measured at
24 and48h. SEMobservation showed that DAEwascharacterized by higher porosity and Oxygen (%)
in the superficial layer and the measurement of the wetting properties showed higher hydrophilicity.
AFMconfirmedthepresenceofahighersuperficialnano-roughness. Microbiological analysis showed
that DAE discs, coated by pellicle’s proteins, were characterized by significantly lower CFUs at
24 and 48 h with respect to the other two groups. In particular, a significant inverse relationship
was shown between the CFUs at 48 h and the values of the wetted area and a direct correlation
with the water contact angle. The biomass at 24 h was slightly lower on DAE, but results were not
significant concerning the other groups, both at 24 and 48 h. The DAE treatment not only modifies the
superficial topography and increased hydrophilicity, but it also increases the Oxygen percentage in the
superficial layer, which could contribute to the inhibition of S. oralis adhesion. DAE can be considered
a promising treatment for titanium implants to counteract a colonization pioneer microorganism,
such as S. oralis.