Dental hard tissues can be demineralized by acids with no bacterial involvement having exogenous or endogenous origin or by acid etching. Exposure of enamel prisms and the lost of interprismatic and prismatic substance were showed by SEM evaluation of enamel when acidic beverages, mouthwashes or etching acid were investigated. As a result of different acidic attacks, high enlargement of the dentinal tubules due to the demineralization of the inorganic part of the dentine and exposure of the collagen matrix were also observed by SEM evaluation. Saliva provides a good protection of dental hard tissues in direct relation to an optimal supply of mineral ions. In our studies morphological assessment of enamel and dentine surface by SEM investigation showed that the severity of demineralizations was lower when saliva was present at the moment of aggressive contact with acidic beverages. Products like toothpastes or gels containing sodium fluoride 0,2%, 0,24% or 0,4%, stannous or aluminum fluoride provided an increased gain of calcium and phosphate ions when they have been applied on dental had tissues in acidic conditions. Association of fluoride with other active ingredients increased the protective effect of the products. Hydroxyapatite in conjunction with calcium lactate or fluoride demonstrated a high remineralization potential of the products when compared to only fluoride containing products. CPP-ACP strategy leaded to increased enamel, dentine and cementum protection against acidic attacks and demonstrated an increased remineralization potential on primary and permanent teeth. The effect was demonstrated to be higher in dentine when compared to enamel and cementum. The consumption of milk, cheese and broccoli before the ingestion of acidic drinks significantly reduced the aggressive potential of these beverages.