Figure 5.

Visualization of linescans from the surface to a depth of 250 µm from the surface. For every linescan, the counts of the target element in >100 µm depth from the enamel surface resembled a horizontal line and were therefore defined as background noise. Counts (y-axis) of respective elements were plotted as a function of depth into enamel (x-axis). Two-dimensional fits were calculated (green lines) with corresponding 95% confidence limits (purple lines). Best fits were an Equilibrium Peak function(1) for CeCl₃ (r² = 0.62; (a)) and NaF (r² = 0.86; (b)) and a Complementary Error Peak function (2) for AmF (r² = 0.97; (c)).