A layer of keratin grows between the nail and the flesh, which is generally considered as thickening of the nail or nail lobes, and is mainly seen in ringworm of the nail in the clinic, and may also be related to psoriasis of the nail, nail lichen planus and other diseases, and can be given antifungal, immunomodulators and glucocorticoid drug therapy after clear treatment. 1. Onychomycosis: It is also called gray nail, which is caused by nail infection with ringworm bacteria. As ringworm causes damage to the nail bed and nail plate, it leads to degeneration of the keratin protein of the nail plate, resulting in thickening of the nails, layering of the nails, and buckling of the nails. 2. Psoriasis nail: it means that psoriasis involves the nail area, which is mainly manifested in the clinic as depression on the surface of the nail, as well as under-nail thickening, nail peeling and nail splitting, and so on. 3. Nail lichen planus: it is a kind of lesion that occurs when lichen planus involves the nails, which can be manifested as thickening of the nail plate, disappearance of the nail plate, uneven surface of the nail plate and roughness of the nail plate and so on. Due to the different causes, the treatment program will also have certain changes, the specific situation needs to be first asked to the doctor after the interview, and then improve the examination, a clear diagnosis, symptomatic treatment.