Citric Acid 1 Dental Enamel 1 Dental Polishing 1 Early erosion Enamel surface 1 Enamels 1 Erosion 1 Erosion time 1 Hardness 1 Human enamel 1 Humans 1 In Vitro Techniques 1 In-vitro evaluation 1 Lunar surface analysis 1 Microhardness 1 Microscopy, Confocal 1 Optical coherence tomography 1 Optical tomography 1 Profilometry 1 Qualitative images 1 Scanning confocal microscopy 1 Surface Properties 1 Surface analysis 1 Surface microhardness 1 Surface profilometry 1 Surface roughness 1 Surface topography 1 Time Factors 1 Tomography, Optical Coherence 1 Tooth Erosion 1