“…Degradation of hydroxyapatite crystals of enamel leading to mineral loss from the sub-surface layer, creating gaps among the enamel rods, and resulting in roughened enamel surface (28) The roughened surfaces cause plaque retention, which increases the demineralization rate and, possibly resulted in many oral diseases (29) . Therefore, surveying surface roughness and surface hardness of enamel is a valuable tool to confirm the efficacy of different remineralizing agents.…”