ABSTRACT Objective: The aim of this study was to evaluate the effects of toothbrushing using a fluoride toothpaste and Aloe vera tooth gel on artificial white spot lesions through the Knoop microhardness (KHN) analysis. Methods: Sound bovine enamel samples (2 mm/diameter and 2 mm/depth) were prepared and immersed in artificial white spot lesion for 24 h. The preparation of artificial white spot lesions was performed by pH-cycling process. The samples were randomly divided into two groups (n=20), according the dentifrice used: containing fluoride (Colgate Total 12) or Aloe vera (Forever Bright Aloe Vera Toothgel). The top surface of samples was submitted to 10,000, 25,000, 50,000 and 100,000 brushing cycles (200 g load) in an automatic brushing machine with abrasive slurry. The KHN analysis were evaluated at baseline, after immersion in artificial white spot lesion and after 10,000, 25,000, 50,000 and 100,000 cycles of brushing. Data were analyzed by two-way repeated measures ANOVA and Tukey tests (p=0.05). Results: The KHN values significantly increased after brushing cycles compared to demineralized means. No significant differences showed for dentifrice factor (p=0.263). However, there were statistically significant differences between groups in cycles of brushing times (p=0.0001). Conclusion: The toothpastes (containing fluoride or Aloe vera) were effective in increasing the superficial microhardness of artificial white spot lesions.