The hair’s natural curl, wave, coil or overall texture pattern is genetically determined by how the hair forms in the follicles. Permed hair only alters hair which extends from the surface of the scalp but does not impact any hair below the scalp.
A hair perm or permanent wave, when properly applied, chemically alters the curl and wave pattern on any hair which has already grown from the roots.
Although the hair is permanently altered to change the texture, any new growth from the roots will revert back to the hair's genetic natural patterns.
A reverse hair perm is performed on previously chemically permed hair in order to restore the hair to it's original hair texture (curls, waves, kinks, coils).
Once a chemical perm is applied to hair the only way to reverse the effects of the perm is to wait for the hair to completely grow out from the roots or to have a reverse hair perm to reintroduce the original hair textures.