## 4 Discussion  
The results presented in this study reject the null hypothesis (H\({}_{0}\)) stating that no difference exists between the area and volume of remaining cement after lingual and buccal multibracket appliance debonding and also between the area and volume of remaining cement after cement polishing of the lingual and buccal multibracket appliance therapies. However, the part of the null hypothesis (H\({}_{0}\)) that states that no difference exists between the area and volume of enamel removed after cement polishing of the lingual and buccal multibracket appliance therapies using a morphometric digital measurement technique is accepted. The results obtained in the present study showed statistically significant higher area and volume of remaining cement after buccal multibracket appliance debonding compared with lingual multibracket appliances, and statistically significant higher area and volume of remaining cement after cement polishing of the buccal multibracket appliance therapy compared with the lingual multibracket appliance therapy. However, no statistically significant differences were shown for the area or the volume of enamel removed after polishing the lingual and buccal remaining cement. Fixed lingual multibracket appliance therapies have been developed and used worldwide in order to avoid the demineralization process of the enamel surface around buccal multibracket appliances and also the formation of unaesthetic white spot lesions [9]. Moreover, fixed buccal multibracket appliance therapies have shown more than 4.8 times the risk of developing incipient tooth decay on buccal enamel surfaces compared with lingual/palatal enamel surfaces associated with fixed lingual multibracket appliance therapies [8]. However, the higher risk of incipient caries developing in the buccal enamel surfaces associated with the fixed buccal multibracket appliance therapies could be associated with a more reduced coverage of the buccal enamel surfaces by the mesh of the fixed buccal multibracket appliances in comparison with the fixed lingual multibracket appliance therapies [11]; however, other factors have been associated with incipient caries developing in the buccal enamel surfaces, such as biofilm formation conditioned by poor hygiene [13]. Nevertheless, the concept which concerns most researchers and clinicians is the SBS capability of multibracket appliance therapies to prevent unexpected multibracket appliance debondings and, hence, possible complications in orthodontic treatment. SBS has reported to be influenced by the design, shape, and size of the multibracket appliances and also by the enamel preconditioning [14]; the ideal SBS range is between 5.8 and 7.9 MPa [15]. Furthermore, the nature of the orthodontic cement has also been reported to influence the SBS score of multibracket appliances; therefore, the same composite resin orthodontic cement was used in both lingual and buccal multibracket appliance therapies selected in this study. However, [PERSON] et al. observed a higher SBS  
Figure 7: Boxplot of the area (**A**) and volume (**B**) of enamel removed after cement polishing of the lingual and buccal multibracket appliance therapies. The horizontal line in each box represents the respective median value of the study groups. Blue represents lingual multibracket appliance and red represents buccal multibrackes appliance. score associated with a fluoride-based cement in comparison with a conventional composite resin-based cement; therefore, the authors recommended fluoride-based cement for bonding lingual multibracket appliances due to its antimicrobial proprieties and the higher SBS score [16]. Moreover, the SBS could also vary depending on the characteristics of the adhesion surface of the multibracket appliances, if it has previous restorations, and their characteristics. Therefore, the adhesion surfaces should be analyzed before bonding to evaluate the necessity of previous conditioning [17].