In Vitro Evaluation of Tooth Enamel Abrasion and Roughness Using Toothpaste with and Without Activated Charcoal: An SEM Analysis

<b>Background/Objectives:</b> Dental enamel constitutes the first barrier of defense against external factors that constantly generate wear and damage. This study aimed to evaluate in vitro the abrasion and roughness of dental enamel using toothpaste with and without activated charcoal and to analyze this under scanning electron microscopy (SEM). <b>Materials and methods</b>: The research design was experimental; 10 enamel blocks were randomly assigned to each group to perform brushing cycles with soft- and medium-filament brushes with two types of toothpaste, one with activated charcoal and one without activated charcoal. A pumice stone with etching acid was used as the positive control and artificial saliva served as the negative control; both were analyzed separately. Roughness was evaluated using a roughness meter and abrasion with an analytical balance. The surface of the enamel blocks of each group was randomly analyzed under an SEM. Statistical analysis was performed using the Shapiro-Wilk test and the homogeneity of variances with Bartlett's test. Student's <i>t</i>-test (two-tailed) was applied to compare tooth enamel roughness and abrasion. <b>Results:</b> Both enamel roughness (<i>p</i> = 0.0016) and abrasion (<i>p</i> = 0.0001) were significantly higher in the groups using activated charcoal paste and medium-filament brushes. SEM observation revealed greater alteration on the surface of the enamel subjected to brushing cycles with activated charcoal paste and a medium-filament brush. <b>Conclusions:</b> The in vitro study showed that the use of toothpaste with activated charcoal increases the roughness and abrasion of tooth enamel, especially when the medium-filament brush is used.