Evaluation of turbo-ER, CR: YSGG laser applications' effect on bond strength between enamel and resin

The aim of this study is to compare the bonding strength of composite resins that bond to enamel surface which treated with burs or Er, Cr: YSGG laser with turbo tip. Additionally in this study, we evaluate which conditioning technique is better in terms of bonding strength for the cavities prepared with Er, Cr: YSGG laser with turbo tip. In these thesis study, four groups created after preparation of enamel samples, obtained from bovine incisor, with bur and Er, Cr: YSGG laser with turbo tip. Then Er, Cr: YSGG prepared surfaces conditioned with three different methods (acid, laser and combination of acid/laser) and these three groups compared with bur prepared and then conditioned with acid. After conditioning enamel samples, composite resins were bonded to surface via adhesive system and evaluated the shear bond strength. After cavity preparation and conditioning procedure, one sample from each group were examined with SEM. According to this study results; bur prepared and then conditioned with acid group (Group FA) and laser prepared and then conditioned with combination of laser/acid group (Group LLA) showed higher bond strength and there was no significant differences among them. Lowest bond strength among all groups was shown by Group LL which laser prepared and then laser conditioned group. In the light of the results within the limitation of this study, conditioning with combination of laser and acid is necessary to obtain an optimum bond strength in turbo- Er, Cr: YSGG laser prepared enamel surface. Keywords: Turbo handpiece, Er, Cr: YSGG laser, Enamel, Shear Bond Strength, Laser etching