Figure 2.

Average fluoride content of the different treatment groups as determined by EDX. For each group, three teeth were used. Shown are the fluoride contents in each individual tooth before and after immersion. In general, there was no significant change in the fluoride concentration after treatments with 250 ppm fluoride. At the very high concentration of 18,998 ppm fluoride (1 mol L⁻¹), tooth enamel showed a highly significant fluoride uptake after the immersion, especially under acidic conditions.