Comparative Evaluation of Enamel Micro-cracks Observed before Bonding and after Debonding of Various Types of Ceramic Brackets: A SEM Study

Abstract

Introduction: Enamel integrity gets affected by the presence of micro-cracks in it and they can further create problems like stains and the accumulation of plaque on the fractured surfaces. Avoiding such iatrogenic damage to the enamel surface has been a constant challenge even with the use of metal brackets. Creating a fracture line in the base of the bracket leads to the formation of a 'weak zone'. This allows the bracket to collapse in a mesiodistal direction when debonding forces are applied rather than shattering the bracket into tiny multiple pieces. Thus, removal of the bracket having such a 'weak zone' created by making a groove in it before bracket removal arguably leaves the major amount of resin on the tooth and therefore causes less stress on enamel. This study plans to evaluate the expected beneficial effect of 'scoring' the base of the ceramic bracket before bracket removal.Aim: To evaluate and compare the occurrence of micro-cracks in enamel observed before bonding and after debonding of various types of ceramic brackets. Results:The difference between scored monocrystalline ceramic brackets and unscored monocrystalline ceramic brackets of both the AO and Ormco groups is not significant statistically (p = 0.096). There is a significant difference in scoring of ARI and enamel micro-cracks development. The difference of length and width between the groups (A and B) is statistically insignificant. Conclusion:Post debonding, there was no difference significantly in the length or width of enamel micro-cracks between AO monocrystalline ceramic brackets (group A) and Ormco monocrystalline ceramic brackets (group B).