All about acne scars

What are acne scars?

Acne scars are the result of your skin healing itself after a breakout.

Typically, when you get a pimple, it gets red and inflamed, and it eventually fades. But for some people, their skin can heal differently than others—and sometimes, their breakouts result in the development of scar tissue.

Acne scars can be of any size, shape, or color. They can look like sunken pits, depressed dents on the skin, raised bumps—or a combination of the three.

What causes acne scars?

Acne scars typically form in phases:

1. Inflammation. When you have a pimple, sebum (or oil), dead skin cells, and bacteria can get trapped inside your pores. This causes an immune response that leads to skin inflammation and tissue destruction. Studies show the severity and duration of acne breakouts can affect whether or not you develop acne scars, which suggests that treating your acne early is the best way to prevent it from developing into permanent scarring.
2. Healing. As the tissue heals, new blood vessels form under the skin (which causes the redness), and your body produces new collagen to provide strength and elasticity to your skin. 
3. Strengthening. Your skin goes through a delicate balance between collagen production and destruction—and the type of acne scar that forms depends on this phase. Atrophic scars form when your body destroys the collagen during the strengthening phase, while hypertrophic and keloid scars occur when your body overproduces collagen (though rare).

The final result is a scar that can be red, raised, or sunken.

What are the different types of acne scars?

Atrophic scars are the most common type of acne scarring. They look like depressions, craters, or indentations in the skin and are caused by the loss of collagen.

• Rolling scars are wide and shallow (4-5 mm) depressions in the skin.‍
• Boxcar scars are round, crater-like, or U-shaped indentations with well-demarcated edges that can be shallow or deep. ‍
• Ice pick scars are narrow (<2mm) deep pits that resemble tiny holes in your skin. 

Hypertrophic scars are raised bumps on your skin that don’t extend beyond the borders of the original wound. These are due to excess collagen and fibrous tissue growth.

Keloids extend beyond the borders of the original wound; they’re firm, red, raised, and can grow over time. These are due to excess collagen and fibrous tissue growth.

Acne marks vs. acne scars

While you may see them as the same, there are some key differences between acne marks and acne scars. Here’s the difference:

Acne marks are discolorations on the skin caused by the previous breakout that has either healed or been treated. They’re commonly called post-inflammatory hyperpigmentation (or PIH, a.k.a. dark acne marks) and post-inflammatory erythema (or PIE, a.k.a. red acne marks).

Acne scars are caused by inflammation and skin injury during a breakout. This can result in tissue loss that leads to skin atrophy (indentation) or aberrant scar formation (raised bumps).

PIH vs. PIE

Post-inflammatory hyperpigmentation (PIH) refers to dark brown spots resulting in increased pigment (melanin) production after inflammation or a breakout. 

Post-inflammatory erythema (PIE) refers to residual pink or reddish patches resulting from trauma and inflammation of the skin. The more inflamed the acne, the higher the likelihood this will appear.

How to treat acne scars

When treating acne scars, the best approach is always one that involves a dermatologist.

Procedural dermatologists, in particular, are specially trained to treat acne scars and can offer a wide range of treatments—from simple peels to laser therapy. They’ll work with you to determine which treatments will be most effective for your skin.

But there’s more to it than just picking the right treatment. Different types of acne scars respond differently to different treatments, so it’s important that you talk to your dermatologist about which treatment (or treatments) are right for you.

Dermabrasion

Dermabrasion involves sanding away layers of skin to help reduce the appearance of your acne scars by removing damaged tissue and promoting new cell growth. This treatment can also be used to treat fine lines and other signs of photoaging.

Laser therapy

Laser therapy uses high-intensity beams of light to vaporize damaged skin cells and stimulate your body’s natural production of new ones, smoothing out acne scars and reducing rough texture.

Chemical peels

Chemical peels can improve the appearance of acne scars by removing or “peeling away” an outer layer of old skin, revealing smoother new skin that appears less scarred.

Microneedling

Microneedling uses a device with multiple needles to create tiny punctures in your skin. This treatment stimulates new collagen formation and smooths out your skin’s appearance, helping improve acne scars, large pores, and signs of sun damage.

PRP

PRP (platelet-rich plasma) therapy uses your blood to create a natural serum rich in growth factors that encourage skin healing, stimulate the repair of acne scarring, and improve overall skin texture by promoting cell regeneration.

TCA CROSS

The chemical reconstruction of skin scars (CROSS) technique uses high concentrations of trichloroacetic acid (TCA)—which breaks down connective tissue fibers—to treat and rebuild atrophic acne scars. The process initially causes inflammation, followed by collagen production and healing, which diminishes the appearance of acne scars and improves skin texture.

Subcision

Subcision is a type of treatment that uses a small surgical instrument (needle or cannula) to break up and release scar tissue under your skin. Subcision is used to treat depressed acne scars and help improve the appearance of atrophic and fibrotic scars.

Dermal fillers

Dermal fillers are injected into the skin to raise depressed acne scars. They’re typically made of hyaluronic acid and other ingredients that help to plump your skin. They work by filling in the depressions left behind by acne scars while smoothing out any irregularities in your skin’s surface.