The aim of the study was to qualitatively investigate the structure of the surface layer of TiO2 on dental implants made of Ti-6Al-4V subjected to different manufacturing treatments. M (machined), B (Al2O3-blasted), E (HNO3\HF-etched), B + E and A (B + E + anodized) implants and a further group receiving the same treatments as the first group with the addition of a final decontamination with cold plasma were included in the study. Examination was performed using micro-Raman spectroscopy. The surface treatments evaluated did not achieve the formation of crystalline TiO2. The increase in the complexity of surface treatment produced a proportional increase in the thickness of amorphous TiO2 oxide. In the B + E group, the plasma treatment enhanced the amorphous oxide thickness of TiO2. The other surfaces treated by plasma decontamination did not show a difference to the respective untreated ones. The investigated surface treatments did not change the crystalline cage of TiO2 in Ti-6Al-4V implants but affected the thickness of the oxide layer. The biological response could be influenced by different oxide thicknesses. Additional information on superficial TiO2 structural organization can be obtained by micro-Raman evaluation of dental implants. Dental implants with B + E + plasma and A superficial treatments allowed the maximum formation of the amorphous oxide thickness.