Chemical peeling is a quite frequent procedure that is used for the treatment of photo aging skin, deep wrinkles and fine lines, acne scars and to improve the skin vitality, tonus and texture. Chemical peeling is the most frequent derma-esthetic procedure in the world. During this procedure there are used different acidic solutions (salicylic acid, lacitic acid, glycolic acid) on the skin in order to stimulate the skin exfoliation, depigmentation and revitalization through promotion of the glucosaminoglicans, fibroblasts and remodeling of the elastin and collagen fibers. This treatment is widely used today as an alternative of lasers or derma abrasions procedures.

Of course, the maximum efficiency would be if you organize a treatment plan and make the combination treatments with other procedures such are fractional laser or derma abrasion. There are three different levels of implementation the peeling procedures. Depth of peeling and the concentration of the substance used are based on the level of damage or photo damage and what is expected by the patient. There are three levels of chemical peeling: superficial, medium, and deep.

Superficial peeling eliminate the superficial cells of the epidermis by causing the necrosis of the epidermis from granulose to basal layer. These peeling stimulate a rapid regeneration of epidermis, eliminate the spots, eliminate the fine lines and improve the wrinkles through the promotions of fibroblasts and regeneration of fibers of elastin and collagen.

The epidermis is composed of keratinized, stratified squamous epithelium. It is made of four or five layers of epithelial cells, depending on its location in the body. It does not have any blood vessels within it (i.e., it is avascular). Skin that has four layers of cells is referred to as “thin skin.” From deep to superficial, these layers are the stratum basale, stratum spinosum, stratum granulosum, and stratum corneum. Most of the skin can be classified as thin skin. “Thick skin” is found only on the palms of the hands and the soles of the feet. It has a fifth layer, called the stratum lucidum, located between the stratum corneum and the stratum granulosum.

The cells in all of the layers except the stratum basale are called keratinocytes. A keratinocyte is a cell that manufactures and stores the protein keratin. Keratin is an intracellular fibrous protein that gives hair, nails, and skin their hardness and water-resistant properties. The keratinocytes in the stratum corneum are dead and regularly slough away, being replaced by cells from the deeper layers.

Stratum Basale

The stratum basale (also called the stratum germinativum) is the deepest epidermal layer and attaches the epidermis to the basal lamina, below which lie the layers of the dermis. The cells in the stratum basale bond to the dermis via intertwining collagen fibers, referred to as the basement membrane. A finger-like projection, or fold, known as the dermal papilla (plural = dermal papillae) is found in the superficial portion of the dermis. Dermal papillae increase the strength of the connection between the epidermis and dermis; the greater the folding, the stronger the connections made.

The stratum basale is a single layer of cells primarily made of basal cells. A basal cell is a cuboidal-shaped stem cell that is a precursor of the keratinocytes of the epidermis. All of the keratinocytes are produced from this single layer of cells, which are constantly going through mitosis to produce new cells. As new cells are formed, the existing cells are pushed superficially away from the stratum basale. Two other cell types are found dispersed among the basal cells in the stratum basale. The first is a Merkel cell, which functions as a receptor and is responsible for stimulating sensory nerves that the brain perceives as touch. These cells are especially abundant on the surfaces of the hands and feet. The second is a melanocyte, a cell that produces the pigment melanin. Melanin gives hair and skin its color, and also helps protect the living cells of the epidermis from ultraviolet (UV) radiation damage.

In a growing fetus, fingerprints form where the cells of the stratum basale meet the papillae of the underlying dermal layer (papillary layer), resulting in the formation of the ridges on your fingers that you recognize as fingerprints. Fingerprints are unique to each individual and are used for forensic analyses because the patterns do not change with the growth and aging processes.

Stratum Spinosum

As the name suggests, the stratum spinosum is spiny in appearance due to the protruding cell processes that join the cells via a structure called a desmosome. The desmosomes interlock with each other and strengthen the bond between the cells. It is interesting to note that the “spiny” nature of this layer is an artifact of the staining process. Unstained epidermis samples do not exhibit this characteristic appearance. The stratum spinosum is composed of eight to 10 layers of keratinocytes, formed as a result of cell division in the stratum basale. Interspersed among the keratinocytes of this layer is a type of dendritic cell called the Langerhans cell, which functions as a macrophage by engulfing bacteria, foreign particles, and damaged cells that occur in this layer.

The keratinocytes in the stratum spinosum begin the synthesis of keratin and release a water-repelling glycolipid that helps prevent water loss from the body, making the skin relatively waterproof. As new keratinocytes are produced atop the stratum basale, the keratinocytes of the stratum spinosum are pushed into the stratum granulosum.

Stratum Granulosum

The stratum granulosum has a grainy appearance due to further changes to the keratinocytes as they are pushed from the stratum spinosum. The cells (three to five layers deep) become flatter, their cell membranes thicken, and they generate large amounts of the proteins keratin, which is fibrous, and keratohyalin, which accumulates as lamellar granules within the cells. These two proteins make up the bulk of the keratinocyte mass in the stratum granulosum and give the layer its grainy appearance. The nuclei and other cell organelles disintegrate as the cells die, leaving behind the keratin, keratohyalin, and cell membranes that will form the stratum lucidum, the stratum corneum, and the accessory structures of hair and nails.

Stratum Lucidum

The stratum lucidum is a smooth, seemingly translucent layer of the epidermis located just above the stratum granulosum and below the stratum corneum. This thin layer of cells is found only in the thick skin of the palms, soles, and digits. The keratinocytes that compose the stratum lucidum are dead and flattened. These cells are densely packed with eleidin, a clear protein, derived from keratohyalin, which gives these cells their transparent (i.e., lucid) appearance.

Stratum Corneum

The stratum corneum is the most superficial layer of the epidermis and is the layer exposed to the outside environment. The increased keratinization (also called cornification) of the cells in this layer gives it its name. There are usually 15 to 30 layers of cells in the stratum corneum. This dry, dead layer helps prevent the penetration of microbes and the dehydration of underlying tissues, and provides a mechanical protection against abrasion for the more delicate, underlying layers. Cells in this layer are shed periodically and are replaced by cells pushed up from the stratum granulosum (or stratum lucidum in the case of the palms and soles of feet). The entire layer is replaced during a period of about 4 weeks. Cosmetic procedures, such as microdermabrasion, help remove some of the dry, upper layer and aim to keep the skin looking “fresh” and healthy.

Peeling with 20-40% glycolic acid, a peeling procedure often referred to as the lunch time procedure’’: a) this procedure is just 1-3 minutes and eliminates several layers of epidermis; b) it smoothness the layers of the skin effectively and rapidly; c) A procedure efficient in acne prone skin and improves the tonus and texture of the skin; d) Effective in treating the acne scars; e) - Increases absorption of local creams and serums

The AHA, BHA (alpha hydroxyl acid and beta hydroxyl acid) is organic acids which realize exfoliation and improve the cell circle-turn over. There are two main results of the application of these acids in the skin: acceleration of cell cycles (which is slow with aging) and improves the stratum corneum smoothness. This peeling reactivates circulation in the skin: a) stimulation of fibroblasts; b) increase and stimulate the glucosamins; c) increases dermal turgor and d) eliminates easy corneal layer of epidermis.

Peeling with salicylic acid which is a simple peeling, very easy to apply and is less time consuming. This is a very effective procedure in treating acne and acne prone skin.

Peeling with 10% trichloracetic acid (TCA) that can be increased in concentration in order to have more benefits from the procedure performed.

During this peeling it helps cleans deeply clogged pores, control and treat effectively severe acne. It also eliminates or make less visible signs of early aging; b) Improves significantly the skin texture and skin discolorations giving an excellent view; c) Smooth and revitalize skin and D) Eliminates the signs of photo aging as dark and white colors.

Medium peeling: For the skin that is more damaged by radiation is recommended the application of medium peeling procedures in order to penetrate deeper the product and the improvement to be seen in the middle layers of the skin. These can cause the procedure to be discomfort (skin redness and desquamation) depending on large areas treated and to the fact that repair of the skin is seen 5-7 days after application of substance that carry peeling.

Acid trichloracetic (TCA) 10-40% is a peeling that improves the fine wrinkles, discolorations and makes the skin smoother and more youthful in appearance. But in the 10-15% concentration peeling does not acts on deep wrinkles or scars. Applying in higher concentration 35-40% it realizes epidermal necrosis without serious systemic toxicity. TCA solution 35-40% is standard for medium peeling of face and hands. In these concentrations should be used by qualified doctors and special care should be carried because it can cause hyper pigmentations and scars.

Glycolic acid 50-70% is also used for the same purposes and same application procedure like TCA peel.

Side effects and special care after application of medium peeling: patients should be prepared that after the peeling procedure they will look bad. During the first two days the skin will look red. On the third or fourth day the skin darkens and on the fifth day it starts the desquamation. Redness persists until day 10-14. Absolute contraindications for applying medium peeling are patients with dark skin because the risk for hyper-pigmentations and those who have used retinoid or local sun radiation because the skin regenerated capabilities are reduce. Contraindications for applying peeling are patients that have herpes simplex and to these patients it is recommended to treat in advance herpes virus with antiviral. Many doctors apply first superficial peeling and then increase the concentration of the product or move on to medium peeling and thus realize a high efficiency through the combination of procedure.

Deep peeling procedure: this procedure is implemented to eliminate deep wrinkles, acne scars and signs of actinic keratosis. It is very aggressive procedure and should be performed by doctors specialized in these procedures. Today the application of lasers and dermabrazion procedure are most frequent and eliminates in this way side effects of this deep peeling. Since the deep peeling can cause hypo pigmentation or skin whitening and skin changes it is recommended to use combinations of deep and medium peeling.

Post peeling procedures is very important especially for medium or deep peeling. Superficial peeling eliminates partly the epidermis and the patient may notice the improvements from peeling and redness after a 48-72 hour period. It’s important to note that the patient during the process of improving after peeling have to keep the skin hydrated by applying the moisturizer creams and protect from the UV radiation through the use of creams with SPF protection factor 50. Certainly the improvement of wrinkles are seen in two months since we all know that the process of remodeling the elastin and collagen fibres need this period of time.

• The presence of Herpes Simplex infection
• The laser treatment procedures carried out recently such as laser depilation, derma abrasion and other procedures that could compromise the structure of the skin.
• Family history to develop keloids or hypertrophic scars.
• Pregnancy
• Allergies and predisposition to post-inflammatory hyper pigmentations.
• Isotretionin treatment.
• Radiation

The peeling procedure is a valuable method for the aged skin, photo aging, acne scars and melasma. It should be performed by dermatologist. Pre peeling preparation of the skin is very important to prepare the skin for this procedure.

• Preparation of the skin starts at least 15 days before the first session.
• Masks used with AHA, BHA or lotions with salicylic acid or lactic acid in lower concentration are recommended.
• Moisturize and protect of the skin, use a hydration cream with at least SPF 50

• Avoid skin friction, masks or hard scrubs
• Prevent Herpes simplex with antiviral.
• Use moisturizing lotions or creams to smooth the skin crusted.
• Check improvement in order to prevent any possible complications and treat it as early as possible.
• Use sun protection creams, minimum SPF 50.