## 3 Results
### \(\mu\)TBS, Degree of Conversion, and Failure Analysis  
The \(\mu\)TBS values at the CAD restoration surface following the application of modified SE adhesives containing ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) NPs are shown in Table 2. The strongest bond of composite to the CAD surface was observed in Group 4 (0.5 wt% ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) + SE) (20.12 \(\pm\) 0.79 MPa). However, the \(\mu\)TBS was weakest in Group 1 (unmodified SE) (15.28 \(\pm\) 0.22 MPa) samples. Intergroup comparison analysis demonstrated that Group 2 \begin{table}
\begin{tabular}{l c c} \hline \multicolumn{1}{c}{**Experimental Groups**} & **Survival Rate CFU/mL** & **Standard Deviation (SD)** \\ \hline Group 1: Unmodified SE (Control) & 0.40 \({}^{\text{A}}\) & 0.09 \\ \hline Group 2: 0.15 wt\% ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) + SE adhesive & 0.19 \({}^{\text{B}}\) & 0.05 \\ \hline Group 3: 0.25 wt\% ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) + SE adhesive & 0.17 \({}^{\text{B}}\) & 0.04 \\ \hline Group 4: 0.5 wt\% ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) + SE adhesive & 0.12 \({}^{\text{B}}\) & 0.01 \\ \hline \end{tabular} Self-etch (SE), zirconia/silver phosphate (ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\)). The different superscript capital letters denote statistically significant differences (_p_ < 0.05).  
\end{table} 
Table 1: The survival rates of _S. mutans_ following the application of modified adhesives containing ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) NPs onto the CAD surface. Figure 3: ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) nanoparticles at various concentrations against _S. mutans_, the pour plate method was utilized. (**A**) presents the colony-forming units (CFU) of _S. mutans_ when treated with Uniformed Self-Etch (Control). In (**B**), the CFU of _S. mutans_ is depicted when exposed to a 0.5% weight (wt%) of ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) nanoparticles. (0.15 wt% ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) + SE) (19.16 \(\pm\) 0.45 MPa), Group 3 (0.25 wt% ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) + SE) (19.85 \(\pm\) 0.57 MPa), and Group 4 demonstrated no significant differences in their attained bond integrity values. (\(p\) > 0.05). However, Group 1 exhibited significantly lower outcomes of bond strength. The failure mode among the experimental groups is presented in Table 3. The major forms of failure identified in Groups 2, 3, and 4 were cohesive, whereas Group 1 exhibited predominantly adhesive failure patterns (Table 3). The FTIR spectra displayed characteristic peaks associated with the conversion of double bonds in both the unmodified self-etch (SE) adhesive (control) and the SE adhesive formulations containing 0.15%, 0.25%, and 0.5% ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\). DC was estimated in SE adhesive loaded with 0.5% by weight ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) (Figure 4); the peak height ratios were measured between the absorbance levels of the aliphatic C=C peak at 1638 cm\({}^{-1}\) and a reference internal peak of the aromatic C=C at 1607 cm\({}^{-1}\). These measurements were taken during the curing process and then compared to those obtained from the unpolymerized adhesive. The highest DC was observed in the control group (unmodified SE (69.85 \(\pm\) 8.37)), whereas DC was comparable in 0.15 wt% ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) + SE adhesive (41.89 \(\pm\) 8.11), 0.25 wt% ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) + SE adhesive (43.74 \(\pm\) 6.91), and 0.5 wt% ZrO\({}_{2}\)/Ag\({}_{3}\)PO\({}_{4}\) + SE adhesive (49.68 \(\pm\) 6.59) formulations (\(p\) > 0.05) (Table 4).