Jessie, however has white spot lesions, which is the earliest clinical sign of the caries process on smooth enamel surfaces. White spot lesions are an indication that the underlying enamel has become decalcified. These are small areas of subsurface demineralization beneath the plaque.

The body of the subsurface lesion may have lost as much as 50% of its original mineral content. Unless steps are taken to reverse this process, the lesion will continue to advance and the previously intact outer layer of enamel will break down creating clinically detectable cavitation.