## 3 Results
### Rubber Dam Isolation and High-Volume Section Reduce the Concentration of Dental Aerosol Particles  
To determine the percentile distribution of dental aerosolized particles generated during the full-crown anterior teeth preparation, DV\({}_{10}\), DV\({}_{50}\) and DV\({}_{90}\) were calculated. After comparison, DV\({}_{10}\), DV\({}_{50}\) and DV\({}_{90}\) of the SS group were significantly lower (\(p<0.05\)) than the RDI group in both vestibular side and palatal side (Figure 3a,b). DV\({}_{10}\) and DV\({}_{90}\) of the RDI group was significantly higher than the RDI + HVE group in the palatal side (\(p<0.05\)) (Figure 3b). In addition, DV\({}_{50}\) and DV\({}_{90}\) of the SS group were significantly lower than RDI + HVE group in the vestibular side (\(p<0.05\)) but no differences were found in the palatal side (Figure 3a,b).  
\begin{table}
\begin{tabular}{c c c c c} \hline \multirow{2}{*}{**Side**} & **Particulate** & \multicolumn{4}{c}{**Volume Fraction (\%) by Group**} \\ \cline{3-5}  & **Matter Size** & **SS** & **RDI** & **RDI + HVE** \\ \hline \multirow{2}{*}{**Vestibular**} & PM\({}_{0.1}\) & 3.85 \(\pm\) 1.33 & [0.52 \(\pm\) 0.25] * & 1.54 \(\pm\) 1.06 \\  & PM\({}_{2.5}\) & 0.00 \(\pm\) 0.00 & 0.93 \(\pm\) 0.93 & 0.03 \(\pm\) 0.01 \\  & PM\({}_{10}\) & 2.02 \(\pm\) 0.77 & 1.45 \(\pm\) 0.92 & [0.33 \(\pm\) 0.04] * \\ \hline \multirow{2}{*}{**Palatal**} & PM\({}_{0.1}\) & 6.56 \(\pm\) 2.37 & [1.11 \(\pm\) 0.56] * & [0.53 \(\pm\) 0.53] * \\  & PM\({}_{2.5}\) & 0.00 \(\pm\) 0.00 & 3.49 \(\pm\) 3.49 & 0.00 \(\pm\) 0.00 \\  & PM\({}_{10}\) & 0.29 \(\pm\) 0.29 & 0.37 \(\pm\) 0.25 & 0.53 \(\pm\) 0.53 \\ \hline \end{tabular} Comparison between groups shows a significant production of ultrafine particles during full-crown anterior teeth preparation. RDI and RDI + HVE strategies reduce these ultrafine particles in both vestibular side and palatal side. No difference was found for any parameter between vestibular side and palatal side. Results are shown as Mean \(\pm\) SEM; \(n=3\). The brackets and the asterisk (*) mean statistical difference when compared RDI and RDI + HVE to the SS group (\(p<0.05\)). Abbreviations: PM, particulate matter; SS, standard suction; RDI, rubber dam isolation; HVE, high-volume evacuator.  
\end{table}
Table 1: Volume fraction of ultrafine (PM\({}_{0.1}\)), fine (PM\({}_{2.5}\)), and coarse (PM\({}_{10}\)) dental aerosol particles.  
Figure 2: Curve distribution of volume fraction of the dental aerosolized particles under 10 \(\upmu\)m. (**a**) The vestibular side shows an increased volume fraction for particles below 0.1 \(\upmu\)m for the SS group, when compared to the RDI and RDI + HVE groups. (**b**) In the palatal side, the volume fraction distribution follows a similar pattern seen in (**a**), except for the RDI + HVE group. Results are shown as mean \(\pm\) standard error of the mean (SEM); \(n=3\). Abbreviations: SS, standard suction; RDI, rubber dam isolation; HVE, high-volume evacuator. X axis (Particle size) is Log\({}_{10}\) scaled.  
To determine the effect of the mitigation strategies on the average size of the particles below 10 \(\upmu\)m for each condition, the Sauter mean diameter (d\({}_{3,2}\)) was determined. For the SS group, the d\({}_{3,2}\) was significantly lower than the RDI group in both vestibular side and palatal side (\(p<0.05\)) whereas the d\({}_{3,2}\) of the RDI group was significantly higher than the RDI + HVE group in the palatal side (Figure 3a,b). For the Dv parameters, no difference was found between vestibular side and palatal side in each group.  
Both mitigation strategies, RDI and RDI + HVE, significantly reduced the concentration of aerosol particles in the vestibular side, when compared with the SS group (\(p<0.05\)) (Figure 3c). In the palatal side, however, only the RDI + HVE showed effectiveness at reducing dental aerosol particles, compared to the SS and the RDI groups (\(p<0.05\)) (Figure 3c). No difference was found between vestibular side and palatal side for any group.