Little white dots/lines in the nail plate are characteristic of leuconychia. In most instances, they are not a worry and are actually 'voids' between the cells that comprise the nail plate.
My concern is the nail that splits up the center. Is this just a high ridge and it splits as it becomes free edge, or is it a split that has developed nito two separate portions of the nail plate with a layer of hardened skin separating the two halves? If it is the latter, there is virtually nothing you can do as the separation is developed in the matrix where the nail plate cells are 'born'.
If it is a high ridge that results in splitting when the nail plate beccomes free edge, you can treat the nails. When thishappens, it is due to the nail plate being very dried out. The nail plate is constantly being 'bathed' by a tidal flow of oils nad moisture that transmit up through the surface from the nail bed. If this flow is diminished, the nail plate becomes dry, and the resulting ridges that you are seeing are actually the 'rails and grooves' between the nail plate and the nail bed that are the 'tracks' upon which the nail plate rides forward.
I would not recommend using any type of nail strengthener at this point. The majority of nail strengtheners give the nail plate its 'illusion' of strength by drying out the nail plate layers (removing the oils and moisture) which can result in 'hard' nails, but will also remove all possibility of flexibility that make the nails tough. Nail strengtheners that work FAST to make your nails 'hard' can cntain more than 2% formaldehyde, and levels higher than 2% can cause sensitivity and allergic reaction.
I would try using a good quality nail and cuticle oil to 'bathe' the nail plate from the outside in. I recommend Solar Oil that is available through fine nail salons or through Ulta Cosmetic outlets natuionwide. You could also use Botanical Oil that is available in the nail department of Sally Beauty Supply. These 2 oils contain jojoba and vitamin E which are excelent for the nails because of the tiny molecular structure of the jojoba and the anti-aging/healing properties of vitamin E. The jojoba oil will penetrate the surface nail plate cells and draw the large molecule of the vitamin E in after it.
Apply a small amount to each nail and massage into the nail plate and the surrounding cuticle at LEAST twice a day and you will see results within 1 - 2 months. Once you have the nails in better 'condition', then I would recommend you try Nail Tek to help strengthen the nails without drying them out again.
Remember, if the nail is already split from cuticle to free edge, there is virtually nothing you can do if the underlying nail bed is growing upward separating the nail plate.
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