## 3 Results
### Biaxial Flexural Strength (BFS)  
Material type, surface finishing, and their interactions had a significant impact on the BFS (\(p<0.05\)) (Table 6).  
The mean BFS values of the surface-finished materials are shown in Table 7. Among the materials, CS and CU demonstrated the highest (158.2 \(\pm\) 3.44 MPa) and lowest (130.6 \(\pm\) 2.53 MPa) BFS values, respectively. Regarding the effect of surface finishing on BFS values, OG specimens demonstrated high BFS (154.75 \(\pm\) 3.05 MPa), and control specimens showed low BFS values (130.62 \(\pm\) 2.93 MPa).  
[PERSON]'s post hoc test demonstrated that most surface finishing protocols resulted in significant differences in BFS from each other (\(p<0.01\)) (Table 8). Contrarily, a non-significant difference was found between OG and MP+PP of LU, CS, and CU materials (\(p>0.05\)). Furthermore, no significant difference was found between MP and control groups of CU (\(p>0.05\)).  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Variation Recourses** & **Sum of Squares** & **df** & **Mean Square** & **F** & **Sig** \\ \hline Materials & 21,212.23 & 3 & 7070.74 & 825.85 & 0.000 * \\ \hline surface finishing & 22,925.81 & 3 & 7641.93 & 892.57 & 0.000 * \\ \hline Materials \(\times\) surface finishing & 1480.94 & 9 & 164.55 & 19.21 & 0.000 * \\ \hline \hline \end{tabular}  
* Statistically significant (\(p<0.05\)).  
\end{table}
Table 6: MANOVA of biaxial flexural strength (BFS).  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Group** & **LU** & **VE** & **CS** & **CU** & **Overall** \\ \hline Control & 136.17 \(\pm\) 2.37 & 123.42 \(\pm\) 3.07 & 141.02 \(\pm\) 4.19 & 121.88 \(\pm\) 2.08 & 130.62 \(\pm\) 2.93 \\ \hline MP & 139.70 \(\pm\) 1.89 & 127.48 \(\pm\) 2.51 & 145.39 \(\pm\) 2.93 & 123.73 \(\pm\) 2.93 & 134.08 \(\pm\) 2.56 \\ \hline OG & 156.75 \(\pm\) 2.76 & 149.93 \(\pm\) 2.59 & 174.17 \(\pm\) 3.83 & 138.16 \(\pm\) 3.03 & 154.75 \(\pm\) 3.05 \\ \hline MP+PP & 156.37 \(\pm\) 4.29 & 146.12 \(\pm\) 1.94 & 172.21 \(\pm\) 2.80 & 138.63 \(\pm\) 2.09 & 153.33 \(\pm\) 2.78 \\ \hline Overall & 147.25 \(\pm\) 2.83 & 136.74 \(\pm\) 2.53 & 158.20 \(\pm\) 3.44 & 130.60 \(\pm\) 2.53 & 143.19 \(\pm\) 2.83 \\ \hline \hline \end{tabular}  
\end{table}
Table 7: Mean BFS (in MPa) of the material group after different surface finishing protocols.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Materials**} & \multirow{2}{*}{**Surface Finishing**} & \multicolumn{4}{c}{**Dunnett’s Multiple Comparison**} \\ \cline{3-6}  & & **Control** & **MP** & **OG** & **MP+PP** \\ \hline \multirow{4}{*}{LU} & Control & 1 & & & \\ \cline{2-6}  & MP & 0.004 * & 1 & & \\ \cline{2-6}  & OG & 0.000 * & 0.000 * & 1 & \\ \cline{2-6}  & MP+PP & 0.000 * & 0.000 * & 1.000 & 1 \\ \hline \multirow{4}{*}{VE} & Control & 1 & & & \\ \cline{2-6}  & MP & 0.011 * & 1 & & \\ \cline{2-6}  & OG & 0.000 * & 0.000 * & 1 & \\ \cline{2-6}  & MP+PP & 0.000 * & 0.000 * & 0.003 & 1 \\ \hline \multirow{4}{*}{CS} & Control & 1 & & & \\ \cline{2-6}  & MP & 0.044 * & 1 & & \\ \cline{1-1} \cline{2-6}  & OG & 0.000 * & 0.000 * & 1 & \\ \cline{1-1} \cline{2-6}  & MP+PP & 0.000 * & 0.000 * & 0.638 & 1 \\ \hline \hline \end{tabular}  
\end{table}
Table 8: Post hoc multiple comparisons for BFS of the materials after surface finishing.