## 4 Discussion  
The aim of this report was to investigate the difference in the SBS to demineralized enamel that had been pretreated with caries infiltrant prior to orthodontic bonding with three adhesives commonly used in relation to fixed orthodontics. The results revealed that the resin infiltration treatment of the demineralized enamel did not impair the SBS comparing it with the SBS on the sound enamel. In fact, \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{3}{*}{**Group**} & \multirow{3}{*}{**Number**} & \multicolumn{5}{c}{**SBS**} & \multicolumn{5}{c}{**SIGNIFICANCE**} \\ \cline{3-10}  & & & **Standard** & **Maximum** & **Maximum** & **ANOVA** & **Tukey’s Test** \\ \cline{3-10}  & & & **Deviation** & & & & **Group 2** & **Group 3** & **Group 4** \\ \hline I & 12 & 11.33 & 4.36 & 3.60 & 17.15 & & 0.757 & 0.915 & 0.000 \\ II & 12 & 12.99 & 5.51 & 7.12 & 24.67 & F = 14.37 & – & 0.369 & 0.001 \\ III & 12 & 10.23 & 2.77 & 5.94 & 14.36 & P = 0.000 & – & – & 0.000 \\ IV & 12 & 20.28 & 3.35 & 16.45 & 25.62 & – & – & – \\ \hline \hline \end{tabular} No statistically significant differences were found among Groups I, II and III. No statistically significant differences were observed among the experimental groups in terms of the ARI values (Table 3).  
\end{table} 
Table 2: Descriptive statistics and shear bond strength (SBS) comparison of four groups. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{3}{*}{**Group**} & \multirow{3}{*}{**Total**} & \multicolumn{5}{c}{**ARI**} & \multirow{3}{*}{**Significance**} \\ \cline{3-3} \cline{5-8}  & & & **Score 0** & & **Score 1** & & **Score 2** & **Score 3** \\  & & **Cases** & & **(Number of** & **(Number of** & **(Number of** & **(Number of** & **(Number of** & **(**Test)** \\  & & & **Cases)** & & **Cases)** & & **Cases)** \\ \hline I & 12 & 6 & 4 & 0 & 2 & \\ II & 12 & 3 & 7 & 2 & 0 & \\ III & 12 & 4 & 7 & 1 & 0 & \\ IV & 12 & 4 & 4 & 3 & 1 & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Fracture modes after SBS testing. it significantly increased the bond strength of one investigated adhesive (Assure PLUS), while it did not have any impact on the other two investigated adhesives. Therefore, the study's null hypotheses had to be partially rejected (Table 2). For the scientific purposes of this research, it was necessary to create consistent artificial lesions in order to simulate in vivo caries development. Hence, artificial demineralized lesions were created according to the recommendations of [PERSON] et al. [21], since it is a widely used and reliable method [6; 10; 23; 24]. The created lesions show uniform dimensions and consistent histological properties [25]. As recommended in other studies, we covered the areas that needed to be preserved from demineralization using an acid-resistant nail varnish [14; 25]. The bonding strength of the adhesive system used should be only large enough to resist the forces that arise in the orofacial region [26]. [PERSON] [27] suggested the average range of the bond strength to be 5.9-7.8 MPa. The mean SBSs obtained in the present report were all satisfactory for clinical use. The demineralized samples were treated with an infiltration system prior to one of three different adhesives being used. The etching in the demineralized groups was performed using 15% hydrochloric acid (HCl). The prior studies [28; 29] showed that the application of 15% HCl generates erosion of caries lesions nearly completely when compared to 35% orthophosphoric acid, thereby allowing for better resin penetration. The 99% ethanol is applied to eliminate the water that is stored inside the microporosity of the lesion body and, hence, to let the resin to penetrate in the lesion body using capillary forces [30]. A recent study reported that preconditioning using a resin infiltrant increased the SBS of different bonding systems on artificial enamel lesions--probably as a consequence of the deeper penetration of the infiltrant into the body of the lesion when compared to the primer or paste [31].