If the ridges run from the cuticle to the free edge, it is simply telling you that the nail plate is extremely dired out or it is a sign of aging. The nail plate rides forward on the nail bed by a series of rails and grooves, much like a train rides forward on its tracks. The rails are on the nail bed and the grooves are on the underside of the nail plate. When the nail plate becomes dried out or is not being 'fed' by a constant upward tidal flow of oils and moisture from the nail bed, the rails and grooves become apparent on the nail plate surface as ridges. The nail plate can become so dried out that the layers begin to peel and split at the free edge.

Simple solution for dried out nails is to apply a good quality nail and cuticle oil to them at least twice a day. Botanical Oil is available in the nail department of Sally Beauty Supply.