Assessment of Enamel Surface Using Scanning Electron Microscope After Debonding Conventional and Self-Ligating Metal and Ceramic Brackets: An In Vitro Study

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Abstract Aims: Minimal enamel loss during bonding and debonding operations is ideal for preserving the enamel surface in fixed orthodontic treatment. This study aimed to assess the enamel surface after debonding conventional and self-ligating metal and ceramic brackets and compare their enamel damage index (EDI) and adhesive remnant index (ARI) using scanning electron microscopy (SEM). Materials and Methods: Thirty-two maxillary first premolar teeth were divided into four equal groups of eight teeth each. According to the type of brackets used, the teeth were set on acrylic blocks that were color-coded: Conventional metal brackets (ORMCO MINI 2000), Self-ligating metal brackets (ORMCO DAMON Q), conventional ceramic brackets (ORMCO SYMETRI CLEAR), and self-ligating Ceramic brackets (ORMCO DAMON CLEAR). After debonding was done using a straight debonding plier, the tooth surfaces were examined by SEM. The ARI and EDI were then evaluated. The Kruskal–Wallis test was used in inferential statistics to determine differences between the groups. The association between the ARI and the EDI was determined using the Pearson correlation test. Results: The ARI revealed lower values for teeth bonded with traditional ceramic brackets, along with higher scores in the EDI. This suggests that the enamel-resin interface was the primary site of bond failure, potentially leading to iatrogenic tooth surface damage from ceramic bracket debonding. Conversely, self-ligating stainless-steel brackets had the lowest EDI scores and higher ARI values, suggesting that the resin-bracket interface was the primary site of bond failure. Additionally, this group showed minimal to no enamel damage, with only a few enamel cracks observed. Conclusion: Self-ligating metal brackets showed the highest ARI scores and lowest EDI scores, whereas conventional ceramic brackets presented with lowest ARI scores and highest EDI scores. The enamel surfaces attached with ceramic brackets showed greater enamel cracks upon SEM analysis.