## 3 Results
### Cell Proliferation  
Results of the trypan blue assay for the estimation of cell proliferation showed the highest mean percentage of live cells in each group on day 3, followed by a consistent decrease on days 7, 10 and 14 (Figure 4, Table 1). Between the groups, and at all time periods of observation, the mean percentage of live cells was highest in HGnF cell cultures with 0.6%, followed by 1.2% and 2.4% blue(tm) oxygen fluid concentrations. The lowest  
Figure 2: Representative photomicrographs of the HGnFs in culture in the control, blue(tm) oxygen fluid and CHX groups: (**A**) Spindle-shaped morphology of cells and (**B**) immunofluorescence staining of F-actin in cells (red color) and nuclei (blue color). (CHX: chlorhexidine).  
mean values were observed in cultures treated with CHX. While the differences in mean cell-proliferation percentage between 0.6% and 1.2% blue(r) oxygen fluid were statistically significant only by day 3, the further differences (days 7, 10 and 14) were not statistically significant. However, the mean values observed with 0.6% and 1.2% blue(r) oxygen fluid were significantly higher than those with 2.4% blue(r) oxygen fluid and CHX at all time periods. Similarly, the mean cell-proliferation percentage in HGnF cells cultured with CHX was significantly the lowest among all groups and at all times.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & & & & & \\ \cline{3-6}
**In Vitro Assays** & \multirow{2}{*}{**Control**} & \multicolumn{3}{c}{**blue®m Oxygen Fluid**} & \multirow{2}{*}{**0.12\% CHX**} \\ \cline{3-6}  & & **0.6\%** & **1.2\%** & **2.4\%** & \\ \hline Cell viability & & & & & \\ Day 1 & 100.00 \(\pm\) 4.27 & 171.82 \(\pm\) 19.71 & 166.08 \(\pm\) 7.41 & 160.54 \(\pm\) 7.15 & 76.14 \(\pm\) 2.11 \\ Day 2 & 100.00 \(\pm\) 6.19 & 108.07 \(\pm\) 7.23 & 104.16 \(\pm\) 9.27 & 102.18 \(\pm\) 4.59 & 56.66 \(\pm\) 3.58 \\ Day 7 & 100.00 \(\pm\) 3.21 & 102.48 \(\pm\) 6.23 & 103.72 \(\pm\) 8.71 & 100.14 \(\pm\) 9.44 & 37.63 \(\pm\) 2.52 \\ \hline Cell proliferation & & & & & \\ Day 3 & - & 133.47 \(\pm\) 10.49 & 102.54 \(\pm\) 15.90 & 80.86 \(\pm\) 12.71 & 58.62 \(\pm\) 3.63 \\ Day 7 & - & 108.75 \(\pm\) 17.88 & 92.03 \(\pm\) 2.84 & 75.43 \(\pm\) 14.31 & 40.24 \(\pm\) 2.11 \\ Day 10 & - & 86.74 \(\pm\) 4.05 & 80.70 \(\pm\) 5.46 & 57.01 \(\pm\) 17.80 & 20.31 \(\pm\) 5.84 \\ Day 14 & - & 75.53 \(\pm\) 13.35 & 72.38 \(\pm\) 14.87 & 50.03 \(\pm\) 12.14 & 19.54 \(\pm\) 2.25 \\ \hline Wound healing & & & & & \\ Day 1 & 29.28 \(\pm\) 2.28 & 12.97 \(\pm\) 2.25 & 14.82 \(\pm\) 2.22 & 21.58 \(\pm\) 7.62 & 8.08 \(\pm\) 0.92 \\ Day 2 & 73.02 \(\pm\) 1.76 & 43.23 \(\pm\) 1.78 & 48.26 \(\pm\) 2.11 & 52.27 \(\pm\) 3.23 & 12.24 \(\pm\) 1.95 \\ Day 3 & 95.64 \(\pm\) 2.58 & 93.74 \(\pm\) 2.14 & 93.74 \(\pm\) 2.14 & 96.24 \(\pm\) 1.70 & 30.51 \(\pm\) 13.26 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Mean values for the in vitro assays, in the different experimental groups, expressed as mean \(\pm\) standard deviation.  
Figure 3: Cell viability of HGnFs following exposure to varying concentrations of topical blue®m oxygen fluid and CHX at different time points. Data are presented as mean percentage values of cell metabolic activity \(\pm\) SD at each time point. Statistical comparisons were made between the control, CHX and different concentration of blue®m oxygen fluid using one-way ANOVA with [PERSON]’s post hoc test (\(p<0.05\); n = 9). CHX: chlorohexidine; * statistically significant difference from control; \(\phi\) statistically significant difference from CHX; *n.s.* not significant.