Chemical peeling, or chemexfoliation, is a skin resurfacing technique that is often used by facial plastic surgeons. Chemical face peeling is not a new technique, as its first applications can be traced back to ancient Egyptian times, when an abrasive mask consisting of alabaster particles, milk, and honey was found to remove wrinkles and produce a smoother skin surface. In today's health-conscious society, many individuals strive to maintain youthful-appearing skin by following sun precautions and by avoiding other risk factors associated with photoaged skin. Facial plastic surgeons are at the forefront of this quest for youthful skin, by being familiar with and applying agents that can help reverse signs of photoaging.

Indications for chemical peel are as follows: First, it may be used to treat facial wrinkles, or rhytids. It is also used to treat pigmentary dyschromias, such as melasma, which is splotchy pigmentation noted on the face following pregnancy. Chemical peel is also used to treat superficial acne scarring, while dermabrasion, another skin resurfacing technique, is the treatment of choice for deeper acne scarring. Some physicians also utilize chemical peel to treat individuals who have had multiple superficial skin cancers arising from premalignant keratotic lesions, to provide a rejuvenated fresh skin surface and to prevent recurrences.

There are essentially three depths of chemical peel: superficial, medium, and deep. Numerous peeling agents are available that can attain each depth of peel. A facial plastic surgeon usually has at least one agent or formula for each depth that he is comfortable and proficient using. Glycolic acid, derived from sugar cane, is perhaps the most commonly used agent for superficial peeling. As the skin ages, the outer layer or epidermis becomes thicker and more irregular, giving rise to a rough, flaky, dry, dull appearance. The underlying dermal collagen atrophies or shrinks and also loses its elasticity, producing the sagging appearance of aged skin. By reversing these changes, chemical peels are able to rejuvenate the aging skin. Investigators have found that glycolic acid can decrease epithelial cell cohesion and also increase dermal synthesis resulting in a more refreshed appearance to the skin.

Various concentrations of glycolic acid are used to attain specifically directed results. For instance, low concentrations (8-15%) are routinely used by the general public in facial skin care maintenance programs. Trained aestheticians or cosmetologists frequently perform 30-50% glycolic acid "mini-peels" to remove the top layer of skin or stratum corneum, resulting in a smoother, more youthful skin. The main advantage of such a "mini-peel" is that there is essentially no "down time" needed for recovery, and individuals can immediately return to school or work. On the other hand, higher concentrations (70%) can produce epidermolysis, allowing the peeling agent to penetrate to a medium depth, which is the equivalent to using 35% trichloroacetic acid (TCA), and this higher concentration carries a greater risk of facial scarring.

Medium depth peels are useful for treating mild photoaging of the skin, including fine wrinkles, pigmentary dyschromias, and actinic keratoses. By definition, this type of peel will penetrate through the upper or papillary dermis, sometimes into the reticular dermis. My choice of agents is 35% trichloroacetic acid (TCA) solution, and I will sometimes pretreat with Jessner's solution. The latter solution contains resorcinol, salicylic acid, lactic acid, and ethanol, and acts as a keratolytic agent to promote deeper penetration of the TCA solution. This type of peel can be performed in the office setting. I generally give preoperative oral and/or intravenous sedation anesthesia, followed by local anesthetic nerve blocks to provide additional comfort. Patients may note a stinging or burning sensation as the peel solution is applied, though this quickly subsides. Postoperatively, patients are intimately involved in a tedious process of cleaning and moisturizing their facial skin as the old skin peels off. Meanwhile, a new skin layer is formed. This new skin will appear intensely pink, as in a sun burn. Most patients are able to wear make-up within 10 days following the procedure, and the redness fades over 4-6 weeks.

Deep peels are utilized to treat moderate to severe photoaged skin. Conditions effectively treated include moderate-deep wrinkles, pigmentary dyschromias, lentigines, actinic keratoses, and superficial acne scarring. My preferred deep peeling agent is Baker-Gordon solution, named after the individuals who pioneered its use for facial cosmetic surgery in the early 1960's. This peel solution contains phenol, which is carbolic acid. The operative and postoperative routine is very similar to that of the medium-depth peel. However, the deeper peel may have a slightly longer healing time; most patients note new, pink reepithelialized skin within 7-10 days, and are usually able to wear make-up by 12-14 days.

While chemical peeling affords an obvious improvement in the appearance and texture of photoaged skin, there are inherent risks, usually with the medium and deep peels, that must be considered. Milia (white-heads from blocked skin pores) and prolonged redness are annoying pitfalls. More serious complications include pigmentation changes, herpetic outbreaks, and scarring. Proper candidate selection and choosing the appropriate peeling agent that coincides best with the individual's skin type will help to avoid these problems.