Fig. 12.

(a) Cross section of a 4 h eroded tooth viewed from the fractured and polished side using dye stained microscopy. Dye penetration into the demineralized channels allows for visualization of the erosion depth. The dark region to right of the arrow is a void between the epoxy and enamel. An erosion of approximately 39 μm is shown. (b) Polarized transmission microscopy of a 6 h eroded tooth from a 250-μm-thickness slice. An erosion of approximately 53 μm is shown. The outer surfaces of the teeth are indicated by the arrows.