## 2 Materials and Methods
Briefly, the cells were washed with saline buffer solution (PBS) without calcium and magnesium ions and treated with a trypsin/EDTA solution for 3-5 min. Later, the detachment solution was removed from the culture vessel, neutralization solution (TNS) was added, and the detached cells were re-suspended by gentle pipetting and moved into a tube containing fetal bovine serum. The cells were then centrifuged at 1000 rpm for 5 min to remove apoptotic or dead cells from the supernatant. The cells were seeded in new sterile culture vessels, on which poly-L-lysine (2 \(\upmu\)g/cm\({}^{2}\)) had previously been deposited at a density of 5000 cells/cm\({}^{2}\). hGEpiC cells at passage 2 were used in the experiments. For adhesion and cell morphology experiments, hGEpiC cells were seeded at 1 \(\times\) 104 cells in 96-well culture microplates, 2 \(\times\) 104 cells in 48-well culture microplates, 4 \(\times\) 104 cells in 48-well culture microplates, the 24-well culture, respectively, 2 \(\times\) 105 cells in 6-well culture microplates that contained the sterilized Ti-based materials or control Coverslip. This cell density was chosen following experiments previously carried out to establish the optimal cell density regarding cell viability and proliferation using the MTS proliferation kit (CellTiter 96(r) Aqueous One Solution Proliferation Assay Kit Test, Promega, Madison, WI, USA. In all the experiments performed, hGEpiC cells were cultured in direct contact with the surface of the studied titanium-based materials for a period of 48 h at 37 \({}^{\circ}\)C and in a humid atmosphere with 5% CO\({}_{2}\). In the adhesion and cell morphology experiments, the hGEpiC cells seeded in the appropriate culture microplates in direct contact with the surface of the studied Ti materials were fixed and marked with specific adhesion markers. To label the actin filaments, the blasted Ti and Ti6 Al4V sample for a 10 s blasting time using white electrocorundum F90, granulometry between 0.15 and 0.20 mm mixed with sintered hydroxyapatite with a granulocyte smaller than 63 \(\upmu\)m, in a ratio of 3:1, under the normal working pressure and 6 bar blasting conditions. \begin{table}
\begin{tabular}{l l} \hline \hline
**Blasting Material** & **Digital Micrographs, 4\(\times\)** \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Digital micrographs for used blasting materials. \begin{table}
\begin{tabular}{c c} \hline \hline
**Blasting Material** & **Digital Micrographs, 4\(\times\)** \\ \hline Glass balls, & \\
0.04–0.07 mm & \\ \hline Olivine, & \\ particle size 0–0.5 mm, & \\
2\(\times\) & \\ \hline Red garnet, & \\ particle size & \\
0.40–0.80 mm, 2\(\times\) & \\ \hline \end{tabular}
\end{table} 
Table 4: Digital micrographs for used blasting materials. The resulting roughness parameter, Ra [\(\mu\)m], for all the experiments carried out, deduced from the roughness profiles, has been centralized in Tables 4 and 5, where the codification represents the following: the first digit is the blasting material and blasting conditions; the second digit is the blasting time in seconds, e.g., blasted Ti, 5-20--blasted with white electroorundum F90, particle size 0.15-0.20 mm--normal working pressure, 6 bar for 20 s.The blasting times were 10, 20, and 60 s, and the coding for blasting material and blasting conditions are as follows:  
Figure 4: Roughness profile of the blank (unblasted) Ti4 Al6V sample. Figure 3: Roughness profile of the blank (unblasted) Ti sample. Comparing the values of Ra for the sandblasted samples to the blank samples, presented in Tables 5 and 6, regardless of the operating conditions, the common trend is an increase in the actual value of the surface roughness for Ti medical grade 4 as well as for the TiAl6V.