Investigation of enamel surface changes in teeth with artificially produced white spot lesions after debonding: an in vitro study

BACKGROUND: This study aimed to investigate enamel surface changes after debonding of teeth with metal and ceramic brackets exhibiting varying severities of white spot lesions (WSLs). METHODS: Forty healthy premolars were divided into two groups based on the use of metal or ceramic brackets. Mild and severe lesions were established to examine the effects of WSLs on enamel damage and bracket type. All the teeth were subjected to the same bonding protocol. The cavitation areas on the enamel surface were examined using stereomicroscopy before application (T0), after debonding (T1), and after finishing (T2). RESULTS: The ceramic bracket group demonstrated significantly greater adhesive residue on the tooth surface after debonding compared with the metal bracket group (P = 0.004). A significant main effect of time was noted, with a substantial increase in the total cavitation area from T1 to T2 (P < 0.001). A significant interaction was observed between time and lesion severity (p = 0.006). When the lesion severity was mild, there was no statistically significant difference in the average total cavitation area between T1 and T2 in either the metal or ceramic bracket groups (p > 0.05). However, when the lesion was severe, the difference was statistically significant in both the metal and ceramic bracket groups (p < 0.001 and p = 0.004, respectively). No significant interaction was found between the time and bracket type (p = 0.214). CONCLUSIONS: A WSL surrounding the entire surface of the bracket carries the risk of cavitation during finishing. Therefore, care should be taken to avoid cavitation in the enamel when removing adhesive residue from these teeth.