Nail edges become empty may be due to onychomycosis, gray nails, fungal leukonychia. 1. Inguinitis: Inguinitis is a relatively common and highly prevalent disease, in the early stage of the onset of the patient will cause pain in the nail area, may also cause a large amount of pus under the nails, resulting in localized swelling and pain and other symptoms. 2. Gray nails: fungal infections can cause gray nails, in the early stage of the onset of the nails will be obviously discolored, with the development of the disease, may also lead to black nails. 3. Fungal leukonychia: patients appear to have a cloudy surface of the nails, and present a white area, if there is a fungal leukonychia, it will lead to softening of the nails, collapse and other symptoms, but also may cause the skin of the nail bed of the nails to flake. Patients whose nails become hollow at the edges are advised to go to regular hospitals as soon as possible for examination and treatment under the guidance of professional doctors.