## 4 Discussion  
GICs are suitable materials for restorative procedures where there are no substantial mechanical requirements, with a highlighted application in \"atraumatic restorative techniques\" (ART) and in minimally invasive restorative procedures [21]. The current paradigm for the treatment of dental caries involves the approach form a biological perspective, involving the use of therapies based on the application of fluorides, calcium, phosphates, or other bioactive components. The surgical-restorative approach is reserved for deep cavitated lesions, following the criteria of the selective removal of carious dentin in combination with the use of materials with remineralizing, restorative, and/or bioinductive potential [22]. Although some studies show that RMGICs are less biocompatible than conventional ionomers [23], others claim that the pulpal inflammatory response and odontoblastic changes produced are similar to those produced by conventional GICs [7]. The adaptation of the restorative material to the cavity walls is essential for a correct sealing of the interface between the material and the substrate to avoid microleakage. Therefore, the study of the adaptation of the material to the cavity walls is an adequate criterion to evaluate interfacial sealing. The use of SEM makes it possible to evaluate the adaptation of the material around the entire perimeter and to accurately measure the possible presence of gaps [5; 24]. One drawback is the possible removal of the material from the cavity walls caused by the drying of the samples and the vacuum of the SEM. However, direct scanning of the samples was selected in this study because indirect epoxy resin replicas showed some disadvantages, such as time consumption. It is also more likely that areas with excess resin or voids will remain. Furthermore, even when specimens can be replicated to preserve fidelity or to withstand the SEM vacuum conditions, it is difficult  
Figure 3: Gap size comparison between the study subgroups. (**a**) Coronal wall, (**b**) axial wall, (**c**) cervical wall, (**d**) mean. Statistically significant differences are indicated with an asterisk: \({}^{\star}p<0.05\); \({}^{\star\bullet}p<0.01\). to determine the extent to which the structures of interest have been masked or altered by the preparation or replication process [25]. In this study, we aimed to evaluate the adaptation of a high-viscosity RMGIC to cavity walls with different dentin conditioning systems followed by the use or absence of SDF/KI. For this purpose, Riva Light Cure(r) was used. This material replaces dentine and chemically bonds to the tooth. Accordingly, following the manufacturer's recommendations, no etching or bonding is required. In addition, since it is a high-density material, it can be used in restorations that need to support load [20]. A study that evaluated the interface between Riva Light Cure(r) and dentin treated with different conditioning systems found that etching with 37% OPA for 5 s or with PA for 10 s reported the presence of resin tags inside the dentin tubules, while when GIC was applied without prior conditioning, an empty interface was found between the restorative material and the dentin [6]. In the present study, it was decided to use these same dentin conditioning times and systems. It should be noted that, although interfacial gaps were found in all samples regardless of the conditioning system used, when OPA was used for 5 s, the gaps were significantly lower in all walls (\(p<0.05\)). This is probably due to the infiltration of the resin component of Riva Light Cure(r) into the partially demineralized dentin. This short treatment time allows partial demineralization without a significant loss of calcium ions that could negatively affect the ionic bonding of the material to the dentin substrate [10]. [PERSON] et al. [9] evaluated the adaptation of conventional GICs and RMGICs with and without prior conditioning with PA, finding similar adaptation with the two types of GICs with and without conditioning.