## 4 Discussion  
In this paper, the debracketing technique was used by positioning the pliers at the base of the bracket and the presence of enamel was not identified either at the level of the ceramic or metal brackets. [PERSON] and [PERSON] found that all brackets analyzed with EDX contain calcium, and by default enamel, in the form of a thin layer, fragments, or even in those where no trace of residual material is visible. The debracketing was performed in this experiment by positioning the pliers at the level of the wings [11]. Further studies that analyzed the presence of calcium on ceramic, metal (SS), and self-ligating brackets confirm that the highest amount of calcium was recorded in ceramic (4%), followed by metal (1.44%), and finally, self-ligating (1.42%). In this study, the debracketing was performed by positioning the pliers at the base of the bracket [12; 13]. Furthermore, in another study comparing the two methods of debracketing metal brackets, i.e., wings and soles, it was found that the ARI\({}_{\text{bracket}}\) score is similar (WM = 66.7%, BM = 68.7%), which assumes that the rupture occurred at either the adhesive-adhesive or adhesive-enamel interface [14]. The two debracketing techniques were expected to result in different ARI scores. However, the ARI score and the presence of calcium were similar in the two methods, despite the difference in force applied, which was previously measured [15]. The explanation for this dichotomy is that the crack is probably initiated  
Figure 11: Density of the elements O, Si, and C on an area of 50 microns. at the level of the adhesive layer and propagated at the bracket-adhesive or adhesive-enamel interface. It should also be taken into account the fact that metal brackets cast with light-curable material have an initially lower adhesion strength at the bracket-adhesive interface than the enamel-adhesive interface because the light-cured resin under the sole of the bracket has reflected light. This is supported by a short-term study that showed that the rupture occurs at the bracket-adhesive interface [16]. Further recent studies [14,15] demonstrated that after a longer period of time, 24 months, the composite is completely polymerized with a strong adhesion force. Another aspect to consider is that the enamel under the sole of the bracket may be affected by decalcification resulting from food debris and poor hygiene that damages the enamel-adhesive bond. The authors claimed that regardless of the method of debracketing chosen, the rupture occurred at the adhesive-enamel interface [15,16]. [PERSON] et al. [17] reported that the biggest part of brackets' failures occurred within the adhesive layer. An analysis of photoelastic stress showed that the force applied to the outer wings of the bracket transfers less stress to the enamel, compared to the force applied to the base of the bracket and the adhesion area, which creates a region of stress concentration in the enamel, thus leading to a separation at the adhesive-enamel interface. Nevertheless, [PERSON] et al. [14] did not find any significant difference between the two possibilities of applying the forceps (on the wings/at the base of the bracket) in terms of calcium score. In this situation, a question arises: is there a correlation between the ARI score and the presence of calcium on the sole of the bracket? One study claims that a thin layer of enamel is removed when the bracket is cut out [18]. This is due to acid etching and the fact that the adhesive material penetrates the micropores produced by this process. Most likely, the partially demineralized enamel around the pores detaches more easily from the tooth and remains adhered to the adhesive material during debracketing. The study was performed in vivo with a treatment duration of 24 months +/ - 3 months. The bracket-adhesive interface is considered to be the most favorable for debracketing, thus leaving most of the adhesive on the tooth surface, as happens at an ARI\({}_{\text{tooth}}\) score of 2 and 3 [19, 20, 21].