Q: One of my customers has a split down the center of her thumbnail that starts at the matrix and grows out with the nail. The condition appeared about three months ago and is on both of her thumbnails. Sometimes she has it, sometimes she doesn’t. What's the deal?
A: Your client appears to have a median nail deformity. Because the split comes and goes, it is unlikely that her condition is caused by a serious underlying disorder – infections and tumors do not come and go. Additionally, median deformities almost always occur on the thumbs.
What is a median nail deformity? It is a change in the nail plate that is produced by a nervous habit. The individual unconsciously presses down on the cuticle of her thumb with the adjacent index finger. Repeated pressure on the soft nail forming underneath the cuticle and proximal nail fold causes a longitudinal indentation down the center of the nail plate. With enough repeated pressure, the nail will split down the middle.
Correcting the deformity isn’t as easy as diagnosing it. Your client must break her habit and resist the urge to press on one nail with another finger. When the pressure stops, the deformity will resolve and the nail will return to normal within four to six months.
By identifying the cause and cure of your client’s condition, you will ensure the client’s respect and gratitude toward you.
Q: Can pregnant women wear artificial nails or are the chemicals used in extension products and nail polish harmful to the fetus, and do glues, polishes, and creams seep through the nails and skin and enter the bloodstream?
A: The question of wearing artificial nails is a valid concern for women of child-bearing age. If a substance is harmful to humans, it is harmful to a fetus. Under normal circumstances, substances gain entrance to the human body through the lungs via inhalation, the stomach through eating and drinking, and the skin through absorption.
Absorption of chemicals through the nails constitutes a minimal potential risk to pregnant women. Fingernails and toenails make up only a small portion of the body’s total absorptive surface area. Accordingly, the amount of material that can be absorbed through the nails is too small to be significant.
The nails absorb very little, a fact which limits fetal danger. Unlike the skin, lungs, and digestive system, nails are not designed to absorb foreign substances and can only do so if the nail is exposed to a substance for a long enough period to enable the material to penetrate it. Most substances that are applied to the nails either contain volatile chemicals that evaporate within a few minutes or are wiped off before absorption can begin. For example, polish remover, nail polish, and acrylics dry in a few minutes; once they’re dry, they cannot be absorbed by the nail.
The nail bed cannot absorb much because it is covered by the nail plate. Also, blood vessels in the nail bed are not designed to absorb foreign substances, unlike blood vessels in the lungs and digestive system.
For these reasons, it is very unlikely that a pregnant woman’s use of nail care products or artificial nails is harmful to her unborn child. It is impossible to say that nothing could happen, but in general, wearing artificial nails poses very little risk to pregnant women.
Skin creams and lotions, on the other hand, may pose a problem for pregnant women because they are absorbed through the skin. Any cream applied to the body or hands during pregnancy can be harmful to a fetus if the cream contains substances toxic to the fetus. However, most moisturizing lotions that you would use in the salon do not contain toxins and can be safely applied during pregnancy. Advise pregnant clients to consult their doctor if they have any concerns about nail or skin care products they use.
--Paul Kechijian, M.D.
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