Effect Of Er, Cr: YSGG And Er: YAG Lasers During Debonding Of Orthodontic Ceramic Brackets: In Vitro Study

Abstract

Introduction: Ceramic brackets debonding is considered a clinical challenge due to their low fracture toughness and high shear bond strength. The shear bond strength must be reduced to facilitate removal. Aim: Debonding polycrystalline ceramic brackets with Er: YAG and Er, Cr: YSGG lasers, and comparing their impacts on adhesive remnant index (ARI) and enamel surface roughness (ESR) to the traditional debonding technique. Materials & Methods: 60 polycrystalline ceramic brackets were bonded to 60 extracted premolars and divided into 3 groups: group 1(control group) contained 12 premolars that were debonded conventionally with a debonding plier, group 2: contained 24 premolars that were debonded with Er, Cr: YSGG laser and was divided into two equal subgroups: group 2A: the samples were irradiated with Er, Cr: YSGG laser at power 9 W & group 2B: the samples were irradiated with Er, Cr: YSGG laser at power 6 W, & group 3: contained 24 premolars that were debonded with Er: YAG laser and was divided into two equal subgroups: group 3A: the samples were irradiated with Er: YAG laser at power 9 W & group 3B: the samples were irradiated with Er: YAG laser at power 6 W. The debonded samples were examined using a scanning electron microscope (SEM) at 20x magnification for ARI scoring and at 60x magnification for enamel surface roughness after polishing. Results: Regarding ARI, the results showed that group 2A had the highest percentage for score 0 and group 3A for score 2, while regarding ESR, group 2B had the highest percentage for score 2. Conclusion: When compared to the traditional procedure, using Er, Cr: YSGG and Er: YAG lasers to debond polycrystalline ceramic brackets may reduce the risk of enamel damage.