A Brief History
Chemical peels offer an excellent option for significantly reducing wrinkling and signs of aging in the face, neck, and décolletage areas. The concept has been around since at least the 1950’s and probably earlier than that. Specialized private formulas were developed by non-medical practitioners that were purported to decrease wrinkles. When these were studied in the early 1960’s the mechanism of action and was discovered and a whole new method of skin treatment was born.
Over the years different compounds were tried until today there is a fixed set of safe and reliable treatments.
How They Work
All chemical peels work by removing some of the outer layers of skin. The depth of the peel is determined by the chemical agent used and the concentration. The deeper layers of the skin respond by regenerating new skin and by increasing the amount of collagen. The result is skin that looks smoother and more youthful.
Alpha Hydroxy Acid Peels
Alpha hydroxy acids are naturally occurring acids and based on chemicals found in apples, milk, sugar cane, or tomatoes In mild concentrations (10% or less) they are sold over the counter. In higher concentrations (20% – 30%) they are usually applied by an aesthetician. AHA’s do a fine job of improving the skin’s texture and can also improve fine wrinkles but they do not treat significant wrinkles. In the lower concentrations they can be used as part of your daily skin care routine. Higher concentrations require periodic re-treatment.
Jessner’s solution uses a mixture of an alpha hyrdoxy acid (lactic acid), a beta hydroxy acid (salicylic acid) and resorcinol mixed with 95% ethanol. Quite the chemistry lesson here. This peel works at the epidermal level and so will also improve the skin texture and minimize small wrinkles. It can also be used as a pre-treatment for a TCA peel. Recovery is rapid.
Trichloroacetic acid, or TCA, was first discovered by a French chemist, Jean-Baptist Dumas in 1839. It is prepared by mixing vinegar (acetic acid) and chlorine. It was widely used in biochemistry but it wasn’t until Dr. Zein Obagi, a dermatologist, began using it that it became the most popular peeling agent. It works by dissolving the keratin in skin and altering the surface proteins.
It’s popularity derives from the fact that it is predictable, safe, and very effective. The depth of the peel can be controlled by adjusting the concentration. A 20% solution of TCA works well as an epidermal peel. Treatment can be done in the office with mild analgesics. The erythema (redness) usually resolves quickly, often in less than a week. Multiple treatments may be necessary.
At higher concentrations – 35% to 50% – a deeper penetration occurs. At this concentration the TCA penetrates to the superficial layer of the dermis. This is considered a medium depth peel and is effective for most facial wrinkles. Anesthesia is often recommended at these concentrations. Concentrations more than 50% are not often used because of the risk of scarring.
Phenol / Croton Oil
Phenol has been around a long time. It was used by Joseph Lister, one of the pioneers of antiseptic surgery. Its method of action is similar to TCA but when it was first used it seemed to always work at the same depth. With the addition of Croton oil it was possible to control the depth of the peel based on the concentration of the oil.
Phenol peels are typically used to treat deep wrinkles, scars, and damaged skin. The procedure requires anesthesia and takes almost two weeks before the skin is healed. It is very effective but is not recommended for dark skinned individuals since pigmentation changes can often occur.