Comedones are small, flesh colored white or dark bumps (papules) frequently found on the forehead and chin of those with acne. They are found at the opening of a sebaceous follicle (pore). A single lesion is a comedo. Comedo is divided into two major categories, open comedo or blackhead and closed comedo or whitehead.
A closed comedo has an obstructed opening to
the skin and may rupture to cause a low-grade skin inflammatory reaction in the
area. The common name for a closed comedo is a whitehead.
An open comedo has a wide opening to the skin
and is capped with a blackened mass of skin debris. It is commonly known as a
Comedonal acne arise when cells lining the sebaceous duct proliferate (cornification), and increased sebum production. A comedo is formed by the debris blocking the sebaceous duct and hair follicle. It is now known that comedonal acne also involve inflammation.
Factors that causes the development of comedonal acne includes:
Comedonal acne or other acne occurs when sebaceous glands of
the skin begin to secrete oil during puberty. These glands are stimulated by
male hormones that are produced in the adrenal glands. Under certain
circumstances, cells that are close to the openings of the sebaceous glands
block the openings. This causes a buildup of oil underneath the skin. Bacteria
then multiply, and cause the surrounding tissues to become inflamed after the
follicle ruptures. If the pore is wide
open, oil becomes oxidized and the oil
changes from white to black, and the result is a blackhead. This is how the two
types of comedonal acne develop.
Follicles have a
wider opening and are filled with plugs of sebum and sloughed off cells which
appear black in colour
form obstruction of
the follicles with the same material but the opening is smaller
The most effective way to prevent comedonal acne is to keep the skin clean and clear of debris that may clog the pores.
"comedolytic" topical medications. These should be applied once or
twice daily as a thin smear to the entire area affected. It may take several
weeks to months before worthwhile improvement occurs. Treatment needs to be
continued long term (sometimes for many years). Consult with a dermatologist if
your acne doesn't respond to over-the-counter treatments.