What Is Nail Denting and What Causes It? (2024)

Denting in the fingernails refers to lines, ridges, or holes in the fingernails or toenails. These dents in the nails can be shallow or deep and found on various parts of the nail in different directions. There are many causes of nail denting including dermatologic conditions and autoimmune diseases that cause skin cell overgrowth and buildup.

Nail Pitting

Dents, ridges, and holes in the nails can occur due to an issue with how the layers in the superficial nail plate develop. This is called nail pitting. The superficial nail plate is the hard part of the nail that is made up of a type of protein known as keratin, which also comprises your hair and skin. The superficial nail plate protects the skin underneath.

One condition often associated with nail pitting is nail psoriasis. Roughly 50% of people with psoriasis also have symptoms that affect their nails. Nail psoriasis is more likely to affect your fingernails than your toenails.

Signs

Other symptoms may include:

• Discoloration of the nail that can be white, yellow, or brown
• Nails that crumble
• Nails that separate from the nail bed, or the skin underneath the nail
• Blood underneath the nails
• Changes in the shape of the nail or deformation of the nail

Causes and Treatments

Although nail pitting can occur in people with psoriasis, research has shown that it is more common in people who have psoriatic arthritis. Psoriatic arthritis typically causes joints to become swollen and inflamed, but it can also cause other symptoms including nail pitting.

There are many other health conditions that can cause nail pitting. Some of them are skin disorders, while others are not. The health disorders that can lead to the development of nail pitting include:

• Sarcoidosis: An inflammatory disease that affects multiple organs
• Pemphigus vulgaris: A rare group of autoimmune diseases that cause blisters on your skin and mucous membranes
• Alopecia areata: An autoimmune disease that causes the immune system to attack hair follicles
• Lichen planus: An autoimmune disease that causes inflammation on the skin and inside the mouth
• Incontinentia pigmenti: A genetic condition that causes skin abnormalities like a blistering rash, wart-like skin growths, and gray or brown patches
• Reactive arthritis: A type of arthritis that develops because of an infection
• Atopic and contact dermatitis: Types of eczema that can cause itchiness, rash, and bumps on the skin

In mild cases of nail pitting, treatment may not be required. This is especially true if the nail pitting isn’t causing any discomfort. Medicinal creams are not always effective because they may not reach the nail bed. However, some cases of nail pitting may be treated with vitamin D₃ and a corticosteroid, a drug that can help reduce inflammation.

The treatment for nail pitting is done by way of treating the disorder that caused it. In the case of nail psoriasis and psoriatic arthritis, the treatment options are the same since nail psoriasis presents the same in both conditions. Typically, topical or injected corticosteroids are used for moderate cases.

Medications that affect how the immune system functions, such as synthetic forms of vitamin D (vitamin D analogs) and calcineurin inhibitors, are also often used to help clear up the condition.

In more severe cases of nail psoriasis with nail pitting, biologics therapy is the first-line option. Biologics are medications made from tiny living components such as proteins, sugars, or DNA.

Treatment options for other disorders that can cause nail pitting include:

• Pemphigus vulgaris: Corticosteroid creams may be used to help reduce inflammation, and immune-suppressing medications are prescribed to help reduce the activity of the immune system, thus decreasing symptoms.
• Sarcoidosis: Treatment for nail changes in sarcoidosis includes oral corticosteroids, topical steroids, and steroid injections directly into the nail bed. The antimalarial medication hydroxychloroquine sulfate has also been used to help treat nail changes.
• Alopecia areata: The medications used to address hair loss for people with this disorder may not help with nail pitting. To treat nail pitting and other nail changes for people with alopecia areata, research has shown that immunosuppressants such as Xeljanz (tofacitinib) and Olumiant (baricitinib) show promise as a potential treatment.
• Lichen planus: The first-line therapy for nail lichen planus is the injection of a synthetic corticosteroid known as triamcinolone acetonide. It can be injected directly into the nails or into a muscle in the body. Retinoids, which act as vitamin A in the body, can also be given orally. In some cases, drugs that suppress the action of the immune system are used.
• Incontinentia pigmenti: Currently, no specific treatment for this disorder is available. The goal of the management of this disease is to ensure that any lesions that occur do not get infected.
• Reactive arthritis: Since reactive arthritis is caused by infection, treatment begins with antibiotics. Once the infection is gone, the symptoms should clear up as well. In some cases, nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, and immune system suppressing medications are used to reduce and manage inflammation.
• Atopic and contact dermatitis: Contact dermatitis occurs when a person comes into contact with an allergen, so treatment typically involves avoidance and removal of the substance that caused the reaction. For atopic dermatitis, treatment can include topical corticosteroids and immunosuppressants.
  

Beau's Lines

Beau's lines refers to an abnormality on the nail plate where indentations form. They were named for French physician Joseph Honoré Simon Beau who first discovered the condition.

Signs

Beau's lines can appear as moat-like depressions or dents on one or more nails. They run horizontally across the nail plate and can affect all fingernails or just a few. They can also affect one or more toenails, most often on the big toe. Beau's lines sometimes have a slight yellow discoloration similar to a fungal infection.

Causes and Treatments

Beau's lines can be triggered by any event that disrupts the nail growth. These can include illnesses and infections such as COVID-19, strep throat, and pneumonia. Injuries that damage your nail matrix such as accidentally slamming a fingertip in a door can also be the cause. Certain skin conditions like eczema and vitamin or nutrient deficiencies such as zinc or protein respectively may also affect nail health and growth.

There's no specific treatment for Beau's lines. Certainly avoiding triggers of an existing skin disorder, such as stress, smoking, alcohol use, and obesity may keep them at bay. While you may not always be able to prevent Beau's lines from happening, eating a diet rich in vitamins and nutrients and staying hydrated can keep the nails healthy and less at risk. That being said, once they form the best course of action is to treat the underlying cause. Keeping your nails short, healthy, and hydrated while addressing the cause will keep them from returning once the nail grows out.

Spoon Nails

Spoon nails, also known as koilonychia, is a condition where the nail takes on a concave or cup-like shape as it grows. This can affect anyone including infants for a myriad of reasons.

Signs

Spoon nails form gradually with the first sign being a flattened nail followed by an indentation deep enough to hold a drop of water in the nail bed. The central portion of the nail then becomes depressed as it grows and the rest of the nail appears elevated. The nails may also appear brittle and thin and feel soft to the touch.

Causes and Treatments

Spoon nails are considered to be a manifestation of something deeper in the body. Chronic iron deficiency is one of the main causes as well as other conditions that can lead to malnutrition such as celiac disease. Endocrine disorders, autoimmune conditions, and nutritional deficiencies are also often causes.

Treating spoon nails involves treating the underlying disease. Getting prompt treatment can prevent the condition from worsening over time. For example, replenishing iron levels can reverse the condition. It's important to work with your healthcare provider to determine the cause and course of treatment. In the meantime, keeping your nails clean and moisturized will help promote growth.

When to See a Healthcare Provider

If your nail denting develops because of an underlying health condition, the severity will vary. In most cases, this isn’t serious and is just a source of cosmetic distress. Severe cases, however, can lead to discomfort and pain that can affect the way you walk and use your hands. Since the nails continue to grow at a slow pace, it can be difficult to determine the cause and control it.

The best thing course of action is to visit your doctor. They will help determine the underlying cause and best course of treatment. In the meantime, try to keep your nails as moisturized as possible, wear protective gloves during certain activities, and avoid any things that may damage them further, such as manicures.

Summary

Nail abnormalities such as pitting, Beau's lines, and spoon nails usually indicate an underlying issue. Skin disorders, nutritional deficiencies and vitamin deficiencies are some of the factors affecting nail health resulting in these dents appearing on the nail.

While no specific treatments are available once this occurs, seeking treatment for the cause can prevent these abnormalities from returning once the nail has grown out. Because our nails can act as a window to our overall health and this could signal a deeper concern within the body, consult with your healthcare provider to determine the cause and best course of action for treatment.