The most important thing to remember is that skin is not autonomous. It's connected to every part of the body and, in turn, every part of the body is connected to it. To fully understand all that's happening, it's necessary to use an inclusive, three-pillar evaluation, looking at all external, internal, and emotional issues that may be involved with the client's skin and body health. Through this comprehensive evaluation, a wellness roadmap can be created to offer an effective, long-term solution. The new trend in the spa industry is to offer inclusive care to address all avenues of health, such as with supplements, medicine, nutrition, exercise, spa treatments, facials, etc., and this multidisciplinary approach requires that we readdress basic skin evaluations.

Chemical Exfoliation
Chemical exfoliation refers to the use of chemical agents to "peel" the skin. Peels are traditionally discussed in terms of the depth of injury (superficial, medium, or deep).

Superficial peels
Alpha hydroxy acids (AHA) are the more commonly used agents in superficial chemical peels. AHAs are naturally occurring acids that include the following: glycolic acid, lactic acid, malic acid, and citric acid. Glycolic acid is the AHA most commonly used, and can be applied to all skin types with minimal risks. It is a mild exfoliating agent that smoothes fine lines and wrinkles and improves skin texture and tone if repeated regularly. The extent of the exfoliation is dependent upon the acid's concentration and pH as well as upon the duration of the application.
Experimental studies have shown that glycolic acid has an anti-aging effect on numerous skin components. This acid diminishes skin aging by increasing collagen synthesis. In photoaged hairless mice, glycolic acid treatments contribute to a significant decrease in wrinkles, an increased thickness of the dermal repair zone, and an increased amount of collagen synthesis.
Peels using low concentrations of trichloro-acetic acid (TCA 15 percent) are also considered superficial.
Superficial peels do not require any significant post-operative care. However, a sun block should be applied to the treated area.

Medium-depth peels
Most of the medium-depth chemical peels are achieved with trichloro-acetic acid (TCA 20 to 35 percent). Indications for medium TCA peels include both medical and cosmetic conditions. Numerous clinical and histological observations underline the effectiveness of TCA peels.
TCA application (degree and depth of penetration) can be controlled easily and accurately. Side effects are uncommon and will depend on the concentration of the acid used (20, 25, 30, or 35 percent) and on the duration of its application.
The post-operative care of medium peels depends on the concentration of TCA used (20, 25, 30, or 35 percent) which is to be determined for every individual case. This will be discussed during the client's introductory visit at the spa.

Deep peels
Deep chemical peels can significantly improve the following lesions: excess of sun exposure, hyperpigmentation, actinic keratoses, and the stigmata of aging (deep wrinkles, laxity of the skin, citrin coloration). Phenol is the strongest chemical agent used for peels and induces a deep peel. Often called a "chemical face lift", the effects of such peels are similar to those of a CO2 laser resurfacing, restoring a youthful appearance to the face with no loss of its harmony.
Deep peels require a general anesthesia, and a recovery period of about seven days. Such peels must be followed by post-operative care. Deep peels may pose a particular risk for patients with a history of heart and kidney diseases.

Microdermabrasion
While chemical peels use chemicals (acids) to exfoliate the skin, microdermabrasion is rather a form of physical, or mechanical exfoliation. Indeed, microdermabrasion uses various kinds of grains or particles to buff away the top surface of the skin, removing dead cells and rejuvenating the skin (increased glow, reduction in pore size, reduction in signs of skin aging). The two microdermabrasion methods are that using crystal versus that not using crystal. Crystal microdermabrasion systems rely on tiny crystals that are blasted onto the skin to perform the exfoliating process. Although the crystal microdermabrasion system is still widely used, the introduction of alternatives has led to a trend away from this treatment system. Diamond microdermabrasion systems operate without the need for crystals. Instead, the exfoliation occurs when a diamond tipped head makes contact with the skin and abrades.

Botox
Botulinum toxin is a purified protein produced by the Clostridium botulinum bacterium, which reduces the activity of the muscles that cause lines and wrinkles to form over time. Botulinum toxin has safely been used in aesthetics to prevent and correct wrinkles for a number of years, enabling an action on both the voluntary and involuntary contraction of muscles. Botox (manufactured by Allergan) has since been considered by practitioners as more than a wrinkle reducer, and has been used more broadly as a tool to improve patients' overall appearance (lifting the eyes, improving the eyebrow arch, etc.). As a result of this broader use of Botox, some practitioners have noticed that with such injection treatments comes a general improvement of the skin.
Botox injections have in the past typically been reserved for the top one third of the face, although more and more practitioners are injecting the lower half as well as the body with great success.
The results of Botox injections are typically seen four to six days after the treatment, and usually last between four and six months. These injections have a cumulative effect, as muscles lose the habit to perform the wrinkle-inducing contractions. As such, Botox is increasingly used on younger patients as a preventative measure.

Fillers
Fillers, also known as restructuring products, are injectables that "fill" wrinkles, lines, and scars. Various types of inert, safe, and volume-inducing products are available. Collagen, hyaluronic acid, and polylactic acid are most commonly used, but autologous fat, acellular dermal allograft, and other products are also available.
Successful treatments with restructuring products may be hindered by inflammatory reactions, potential allergies, and asymmetries if the products are not well injected. Other contraindications include all so-called collagen-related diseases (chronic inflammatory diseases), a known predisposition for allergies, and pregnancy.

Collagen
Collagen is a polypeptide substance that is the main constituent of the skin, of connective tissue and of the organic substance of bones and teeth. Age, disease, injury, and sun exposure can weaken the skin's endogenous collagen, thus altering its appearance. Injections of exogenous collagen can restore the skin's youthful appearance.
Zyderm and Zyplast are most commonly used for the treatment of aging skin, lip augmentation, scars, and facial atrophy. Both of these products are degradable, and to maintain best results, reinjections are necessary every six months on average. More recently, autologous collagen has been proven to be an effective, longer-term collagen filler for cosmetic imperfections.

Hyaluronic acid
Hyaluronic acid is a natural occurring mucopolysaccharide that forms the extra-cellular matrix. This acid possesses many of the typical characteristics of a restorative product and provides new possibilities for the effective treatment of facial wrinkles, for the correction of the cutaneous contour, and for the increase of lip volume.
Restylane and Juvederm are the most common forms of hyaluronic acid used. Both are produced biogenetically (through bacterial fermentation and stabilization). Restylane and Juvederm Ultra injections tend to last about four to six months. Perlane and Juvederm Ultra Plus injections are ideal for the deeper folds. These products are both more viscous and tend to last slightly longer, between six and eight months. Juvederm Ultra and Juvederm Ultra Plus are manufactured by Allergan, while Restylane and Perlane are manufactured by Medicis Corporation.

Polylactic acid
Polylactic acid is a type of degradable restorative product. During its presence in the dermis, this molecule induces the production of collagen by fibroblasts. This contributes to the filling of wrinkles and of the excavated facial areas. The effects of this product will last between one to two years. The main brand of polylactic acid available on the market is Sculptra (by Sanofi Aventis, known as New-fill in other parts of the world).

Lasers
The word LASER is an acronym for "Light Amplification by Stimulated Emission of Radiation." The history of medical lasers begins in 1960, when the first laser – a ruby laser – was developed by Dr. Maiman. Since then, new lasers have been developed, and existing lasers have been continually improved upon.
Typically, lasers are discussed in terms of six parameters, of which the four most relevant to treatment are:

Wavelength (nm, nanometers)
The laser's wavelength is determined by the lasing medium and is chosen based on the targeted chromophore. Although most lasers used in dermatology emit rays contained in the visible light range of the spectrum (400 to 700nm), some emit in the infrared range (1,000 to 11,000nm). Lasers that emit in the ultra-violet range (150 to 350nm, excimer lasers) are also used in dermatology, primarily for the treatment of psoriasis.

Pulse duration (ns, μs, ms, nano-, micro-, millisecond)
Pulse duration is the duration of each laser pulse (not relevant for continuous wave lasers). This duration will depend on the thermal relaxation time (see below) of the target.

Spot size (mm, millimeters)
The spot size represents the diameter of the laser beam emitted. This diameter will influence the penetration of the beam in the tissue. Indeed, the larger the spot size, the less the scattering of the photons inside the tissue, leading to a deeper penetration of the laser beam. A larger spot size will also enable a faster treatment time, as each pulse covers a greater area.

Fluence (j/cm2, joules per centimeter square)
Fluence measures the energy delivered per unit area. As the fluence increases, so does the destructive force of the beam. Depending on the laser used, the fluence will vary between three to 150 j/cm2.

Chromophores
Chromophores are molecules responsible for the color of a mass and absorb the energy of specific wavelengths. The most common chromophores encountered in aesthetics are hemoglobin (which is targeted when vascular lesions are treated, including rosacea and leg veins), melanin (which is targeted during hair removal treatments and for the removal of brown spots), tattoo ink (which is targeted during tattoo removal treatments), and water (which is targeted in most rejuvenating laser treatments). Based on the theory of selective photothermolysis, developed by Dr. Rox Anderson, the concept of a laser is to specifically target a chromophore (e.g. a hair follicle) without destroying the surrounding tissue (i.e. healthy, hairless skin).

Intense Pulsed Light devices (IPLs)
IPL devices are not lasers. The two are indeed different from both a technology perspective and from a treatment perspective. The main difference between an IPL device and a laser is that the light of the former is non-monochromatic. While in the case of lasers, the lasing medium produces a single wavelength, and thus targets a single chromophore; IPL devices function with filters. Non-monochromatic light is created by an energy source, then filtered. While IPL filters enable the therapist to select the range of wavelength best suited to a specific treatment, they do not enable the therapist to select a single wavelength: for example, a 585nm IPL filter will filter out shorter wavelenghts, but not longer wavelengths. The therapeutic consequence is that a wider range of conditions can be treated with a single IPL device versus with a single laser (for example, both redness and brown spots can be treated with an IPL). In other words, an IPL is less specific in its effects. Some will argue that this lack of specificity makes IPL devices less effective, and more difficult to use (thus operator error is more likely).

Light Emitting Diodes (LEDs)
LEDs are neither lasers nor IPL devices. The main difference between LEDs and lasers is that the light of the former is not collimated (but it is monochromatic); this means that the energy is divergent rather than focalized. The therapeutic consequence is that LEDs have a much lower energy output than lasers. LED treatments are still effective, however. Indeed, while the purpose of a laser is to selectively destroy a specific target (hence the need for a high energy output), the purpose of an LED is most often to stimulate (rather than destroy) a specific target, something that can be achieved with a lower energy. The main applications of LEDs are rejuvenation, photo-dynamic therapy, and cellulite reduction.
While the scope of advanced aesthetic treatments discussed in this article is not exhaustive, this overview does illustrate the increasingly broad therapeutic choices that face the beauty consumer today. Whether or not you decide to integrate some or all of these advanced treatments in your menu, your clients will come to you with questions and look to you for advice. Hopefully this overview has provided you with the tools to answer these questions and educate the consumer.

Ada Polla Tray, who was recently featured on the cover of Business Week Small Biz, is the co-creator of the Swiss antioxidant skin care line Alchimie Forever. Tray has developed the line's brand and visibility, has established international distribution for the products, and has driven the company's double-digit annual revenue growth. She is on the editorial board of PCI Magazine, a committee member of ISPA and a speaker at leading universities and industry conferences. Tray graduated in the top five percent of her MBA class at Georgetown University in 2004 and received her Magna cum Laude BA at Harvard University in art history and political science in 1999.