## 2 Materials and Methods
### Restoration Stage and Bond Strength Measurement  
The application was conducted on both the sound (SD) and eroded (ED) flat dentin surfaces using 37.5% orthophosphoric acid for a duration of 15 s, followed by a 15-s rinse under 2 bar air pressure from a 10 mm distance and subsequent drying. In the experimental groups, MMP inhibitors of 2% CHX (Cavity Cleaner, Bisco Inc., Schaumburg, IL, USA) \begin{table}
\begin{tabular}{c c c c} \hline \hline  & & \multicolumn{2}{c}{**Bond Strength (24-h)**} \\ \cline{3-4}
**Dentine Type** & **Different Amounts** & **20 s** & **30 s** \\ \cline{3-4}  & **of a-Tomatine \({}^{\star}\)** & **Mean \(\pm\) Sd** & **Mean \(\pm\) Sd** \\ \hline \multirow{4}{*}{
\begin{tabular}{c} Sound dentine \\ (n = 1) \\ \end{tabular} } & 0.75 mM & 14.07 \(\pm\) 4.31 & 14.12 \(\pm\) 6.01 \\ \cline{2-4}  & 1 mM & 25.43 \(\pm\) 8.96 & 25.38 \(\pm\) 8.48 \\ \cline{1-1} \cline{2-4}  & 1.5 mM & 43.17 \(\pm\) 7.40 & 42.55 \(\pm\) 16.86 \\ \cline{1-1} \cline{2-4}  & \(p\) & 0.001 ** & 0.001 ** \\ \hline \hline \end{tabular}  
* According to [PERSON] and [PERSON] et al. [10; 22], selecting for a-tomatine’s uM.  
\end{table} 
Table 1: Evaluation of pilot study to calculate the amount and application time of tomatine. and 1.5 uM of tomatine were administered for 20 s. Conversely, only Optibond FL (Kerr, Orange, CA, USA) was employed in the control groups, adhering to the recommendations of the manufacturing company. Following the elimination of any excess inhibitory agent using an absorbent pellet, the Optibond FL application in the experimental groups was finalized. A microhybrid-based composite material was polymerized onto the flat dentin surface with the assistance of a halogen light (a minimum intensity of 400 mW/cm\({}^{2}\) and 40 s). The experimental samples belonging to individual subgroups were stored in an incubator at 37 \({}^{\circ}\)C in distilled water until the testing phase. After the aging process, dentin sticks were affixed at both extremities utilizing a cyanoacrylate adhesive (Pattex, Henkel, Dusseldorf, Germany) to a testing device (Microtensile Tester, Bisco, Inc., USA) to assess the microtensile bond strength. This involved the application of a tensile force of 500 N at a speed of 1 mm/min within a universal testing apparatus until the point of failure, with the resulting uTBS values measured in MPa. The failures that occurred during the microtensile bond strength analysis in the dentin sticks were scrutinized under \(\times\)30 magnification using a stereomicroscope (Olympus SZ 6.1, Munster, Germany). The identified failure modes were categorized into three distinct types: adhesive/mixed, cohesive in dentin, and cohesive in composite. Detailed information regarding the utilized materials and their compositions is provided in Table 2. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Material** & **Composition** & **Manufacturer and Batch Numbers** \\ \hline \multirow{3}{*}{Citric acid} & Citric acid monohydrate & Merck, KGaA, Darmstadt, Germany \\  & C\({}_{6}\)H\({}_{8}\)O\({}_{7}\)H\({}_{2}\)O & (5949-29-1) \\ \hline Dimethyl sulfoxide & Dimethyl sulfoxide & \\ extra pure & C\({}_{2}\)H\({}_{6}\)OS & Merck, Sigma Aldrich, Germany \\ \hline \multirow{4}{*}{Saliva} & 0.002 g of ascorbic acid, 0.58 g & \\  & of NaCl, 0.17 g of CaCl\({}_{2}\), 0.16 g & \\ \cline{1-1}  & of NH\({}_{4}\)Cl, 1.27 g of KCl, 0.16 g & Produced in the lab as artificial \\ \cline{1-1}  & of NaSCN, 0.33 g of KH\({}_{2}\)PO\({}_{4}\), & \\ \cline{1-1}  & and 0.34 g of Na\({}_{2}\)HPO\({}_{4}\) for 1 L & \\ \hline Etching dental gel & 37.5\% phosphoric acid gel & Kerr, Gel Etchant, Orange, USA (5887888) \\ \hline \multirow{2}{*}{Cavity cleanser} & \multirow{2}{*}{2\% chlorheximide digluconate} & Bisco, Inc., Schaumburg, IL, USA (1900000744) \\ \hline \multirow{4}{*}{Otitibond FL} & Primer: HEMA, PAMM, GPDM, water, ethanol, photoinitiator Adhesive: TEGDMA, DMA, GPDM, HEMA, BIS-GMA, filler, photoinitiator & Kerr, Orange, CA, USA (26684) \\ \cline{1-1}  & & \\ \end{tabular}
\end{table}