Morphological changes on enamel after irradiation with femtosecond pulsed laser

摘要

The purpose of this study was to investigate the morphological change of enamel surfaces after irradiated with a femtosecond (fs) pulsed laser at 90 uJ and 20 mm/s at different conditions of focus (surfaces, 1 mm subsurfaces and 2 mm subsurfaces). Morphological changes of surfaces and subsurfaces were evaluated under a scanning electron microscope (SEM) and a polarized light microscope. The surface analysis under SEM demonstrated the effect of laser on enamel abrasion only on the focus at surfaces. Change at subsurfaces was observed in all specimens that were irradiated at subsurfaces by SEM. Polarized light properties of enamel demonstrated varied changes with different degrees depending on the focus conditions compared with non-irradiated surfaces. In conclusion, the fs-pulsed laser caused a change on enamel subsurfaces.