Considering the 1% of significance, in the statistical analysis, we observed a direct relationship between TF1, TF2, TF3 and TF4 indexes with an increased risk of presenting fluorosis was observed when brushing was done with adult toothpaste (OR:0.113, 0.111, 0.160, 0.042; p=0,000) and if there was an intake of it (OR: 25.392, 31.725, 23.159, 31.657; p=0,000). Here, MLX is linked to dental fluorosis.