The purpose of this study was to evaluate which of the techniques and acids included in this in vitro research can induce artificial caries lesions in the most natural way. White spot lesions were created using six different demineralizing solutions in liquid form (lactic acid; orthophosphoric acid; formic acid; and an acid solution that contains calcium chloride, sodium phosphate and acetic acid) and gel form (hydrochloric acid and orthophosphoric acid). Radiographs, photographs and readings with a DIAGNODent™ pen, VITA Easyshade and a scanning electron microscope (SEM) were made in the initial situation, after 30 min, 1 h, 24 h and 96 h of demineralization. The total color change (ΔE) values in most cases presented statistically significant differences. SEM images showed different aspects of the enamel surface for each type of acid. Only in the case of exposed dentine did the DIAGNODent™ pen record significant differences. There was no noticeable radio-translucency of the teeth treated for a short period of time, but after 24 h, the absence of enamel and major demineralization of dentine were visible. Acids in the liquid state can penetrate and demineralize dental structures deeper than those that are more viscous. This study should be repeated with a protocol that includes remineralization. Using weaker acids would be another direction that could lead to more interesting findings.