What Causes Koilonychia?
Petroleum Exposure
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Exposure of petroleum-containing products to an individual's nails over an extended duration can cause them to develop nail deformities, including koilonychia. The nail bed and nail matrix epithelial cells are both responsible for the formation of the nail plate, nail, and nail bed. The area underneath the nail plate and the nail fold are the most vulnerable areas when it comes to chemical exposure to an individual's fingernails. In the area of its free margin, chemical substances can penetrate underneath an individual's nail plate and nail bed. Most occupations involving exposure to petroleum-containing substances fall under the category of cosmetology, including hairdressers, beauticians, barbers, and nail technicians. Chemicals such as petroleum can also induce a condition called allergic dermatitis in the periungual skin regions, causing repeated inflammation to a patient's nail bed. Any chemical substance that results in an inflammatory response in an individual's nail matrix or nail bed can cause the nail to become distorted or deformed. Precautions should be taken by those who work closely with harsh chemicals that contain petroleum, such as wearing protective gloves on the hands.
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