## 4 Discussion  
As replacement of failed restorations accounted for more than half of restorations placed [29], the decision to replace failed restorations often necessitates the removal of sound tooth structure; with subsequent increase in the size of prepared cavity and weakening of the remaining tooth \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & & **X-Tra Fil** & **Admira Fusion X-Tra** & \(p\)**-Value** \\ \hline \multirow{5}{*}{**FBM+**} & **OIL** & \(21.5\pm 4.8\) A & \(12.9\pm 2.1\) B & 0.001 \\  & **M** & \(28.3\pm 4.3\) A & \(11.9\pm 1.8\) B & \(<\)0.0001 \\  & **FBM+** & \(25.1\pm 3.6\) A & \(11.6\pm 2.7\) B & \(<\)0.0001 \\  & **S/FBM+** & \(27.4\pm 5.0\) A & \(17.0\pm 3.7\) B & 0.001 \\  & AB & \(14.1\pm 2.2\) A & \(15.8\pm 3.3\) A & 0.275 \\  & **S/AB** & \(19.3\pm 4.1\) A & \(11.6\pm 2.0\) B & 0.001 \\  & **CRS** & \(26.3\pm 5.1\) A & \(16.7\pm 2.3\) B & 0.001 \\  & **S/CB** & \(25.2\pm 3.0\) A & \(12.9\pm 2.4\) B & \(<\)0.001 \\ \hline \multirow{5}{*}{**FBM+**} & **OIL** & \(16.2\pm 1.9\) A & \(9.6\pm 1.4\) B & \(<\)0.001 \\  & **M** & \(10.9\pm 2.8\) A & \(7.5\pm 1.3\) B & 0.012 \\ \cline{1-1}  & **FBM+** & \(17.3\pm 2.1\) A & \(7.9\pm 1.1\) B & \(<\)0.0001 \\ \cline{1-1}  & **S/FBM+** & \(21.2\pm 2.9\) A & \(8.4\pm 0.7\) B & \(<\)0.0001 \\ \cline{1-1}  & **AB** & \(10.4\pm 2.2\) A & \(8.6\pm 1.2\) A & 0.060 \\ \cline{1-1}  & **S/AB** & \(15.3\pm 2.1\) A & \(8.1\pm 1.4\) B & \(<\)0.0001 \\ \cline{1-1}  & **CRS** & \(20.5\pm 3.5\) A & \(11.1\pm 2.5\) B & \(<\)0.0001 \\ \cline{1-1}  & **S/CB** & \(18.6\pm 2.6\) A & \(12.7\pm 1.2\) B & \(<\)0.0001 \\ \hline \end{tabular}  
Means with same superscript uppercase letters within each row are not statistically significant at \(p=0.05\).  
\end{table} 
Table 4: Mean \(\pm\) standard deviation for the effect of material within each surface treatment and storage time on \(\upmu\)SBS. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **24 h** & **6 Months** & **Percentage Drop** & \(p\)**-Value** \\ \hline
**OIL** & \(12.9\pm 2.1\) abcA & \(9.6\pm 1.4\) bcB & \(25.6\%\) & 0.003 \\
**M** & \(11.9\pm 1.8\) bcA & \(7.5\pm 1.3\) cB & \(37\%\) & \(<\)0.0001 \\
**FBM+** & \(11.6\pm 2.7\) cA & \(7.9\pm 1.1\) cB & \(31.9\%\) & 0.005 \\
**S/FBM+** & \(17.0\pm 3.7\) aA & \(8.4\pm 0.7\) cB & \(50.6\%\) & \(<\)0.0001 \\
**AB** & \(15.8\pm 3.3\) abA & \(8.6\pm 1.2\) cB & \(45.6\%\) & \(<\)0.0001 \\
**S/AB** & \(11.6\pm 2.0\) aA & \(8.1\pm 1.4\) cB & \(30.2\%\) & 0.002 \\
**CRS** & \(16.7\pm 2.3\) aA & \(11.1\pm 2.5\) abB & \(33.5\%\) & \(<\)0.0001 \\
**S/CB** & \(12.9\pm 2.4\) abcA & \(12.7\pm 1.2\) aA & \(1.6\%\) & 0.860 \\ \hline \hline \end{tabular}  
Means with same superscript lowercase letters within each column and same superscript uppercase letters within each row are not statistically significant at \(p=0.05\).  
\end{table} 
Table 3: Mean \(\pm\) standard deviation of \(\upmu\)SBS in MPa for the effect surface treatment within each storage time, and the effect of storage time within each surface treatment; and percentage drop in \(\upmu\)SBS of Admira Fusion X-tra resin composite. structures [30]. Term \"repair\" is considered when adding material is decided to repair the defect either without additional preparation or with minimum preparation including tooth and/or defective restoration [7]. Bulk fill resin composites were developed aiming to reduce the chair-side time wasted during the application of several increments as in conventional resin composites [31]. Admira Fusion X-tra is the bulk version of Admira Fusion. It is an \"organically modified ceramic\" that contains no classic monomers such as Bis-GMA, TEGDMA or HEMA to improve its \"biocompatibility\". Its chemical structure is based on silicon oxide innovative technology, not only in fillers, but also for the resin matrix (Admira Fusion and Admira Fusion X-tra, Technical Product Profile, VOCO GmbH). From the results of this study, the null hypothesis must be rejected.