Acne scars can form as a result of inflamed acne blemishes, or picking at any acne lesions.
Inflammatory acne is caused when the oil gland/hair follicle unit becomes overloaded with excess oil, dead skin cells and bacteria. The unit swells, which causes a break in the follicle wall. If the lesion is shallow, it can possibly heal quickly. However, if there is a deep break in the unit wall, infected material can spill out into the surrounding tissue and create a deeper lesion. The skin attempts to repair these lesions by forming new collagen fibers. These repairs are not as smooth and flawless as the original skin, resulting in acne scarring.
Additionally, picking at any acne lesions and causing scabs that are repeatedly torn from the skin can lead to scarring.
Almost 95% of patients with acne will experience some form of acne scarring. There are no specific risk factors, but some believe genetics plays a role.
There are two main types of acne scars:
Hypertrophic or keloid scarring develops when the body produces too much collagen as acne wounds heal, resulting in a mass of raised tissue on the skin's surface.
Atrophic or depressed scarring develops when there is a loss of tissue. There are two common types of atrophic scarring. "Icepick" scars are usually small, yet obvious holes in the skin. "Boxcar" scars are depressed areas, usually round or oval in shape with steeply angled sides, similar to chickenpox scars.
Physical examination is needed to diagnose the type of scarring and develop the most appropriate treatment plan.
The most common treatment for both keloids and hypertrophic scars is a steroid injection that decreases the immune system’s overproduction of collagen. This can soften and flatten the scars but may take multiple injections over time.
Laser treatments with a resurfacing laser can treat atrophic scars by causing intentional injury and collagen stimulation. Other lasers can be used to target the vascular components of scars in an effort to reduce redness.
Other treatments of atrophic scars include: SkinPen treatments , chemical peels , minor skin surgeries, and dermal fillers.
The most important way to prevent new acne scarring is to treat the underlying acne. The following are ways to decrease the appearance and worsening of existing acne scarring:
Sun protection is critical. Overexposure to the sun can darken scars and make them look more prominent. Sunscreen, preferably zinc-based with an SPF of 30 (or higher) should be worn everyday. SPF in make-up alone typically does not provide sufficient coverage.
Avoid irritating inflamed skin. Over-washing or scrubbing scarred areas can further reduce skin elasticity and heighten the appearance of the scar.
Never pick at scars. Creating scabs that are repeatedly picked off can create a deeper scar. Additionally, bacteria from unwashed fingers and nails increase the risk of additional cysts forming, leading to the development of a larger scar.