Aesthetic and cosmetic dermatology

ARTICLE

Auteur(s) : M Kerscher

St. Williams

Definitions

Dermocosmetics/cosmeceuticals are a category of cosmetic products, which integrate dermatological and pharmaceutical considerations and meet certain criteria concerning quality and documentation – objective evaluation and verified benefits with low risks of unwanted side-effects. They fall between cosmetics and pharmaceuticals but are subject to many of the regulations applicable to drugs.

Impact

Cosmetic dermatology not only has changed the face of traditional dermatology but also has had a documented impact on patients’ quality of life. Many individuals feel a distinct improvement in their psychological and physical well-being after cosmetic treatments. The majority of patients are reluctant to undergo invasive aesthetic medical therapy such as surgical face lifts. At the same time, increasing numbers are showing interest in topical preparations with proven benefit, and minimally invasive procedures such as soft tissue augmentation and botulinum toxin injections. As a result, the demand for non-surgical cosmetic procedures has grown considerably. Patients want to look their best; dermatologists can help them to realize this aim.

Activities

For the practical application of any of these activities, a sound theoretical background is vital not only in general dermatology, but also in particular aspects concerning pathogenesis, prevention and therapy of cosmetic disorders. This theoretical basis should cover:

• – Specific anatomy and physiology of the skin and its appendices;
• – Pathology of cosmetic disorders (e.g. intrinsic and extrinsic skin ageing, signs of ageing of hair and nails);
• – Endocrinology;
• – Classification of skin types and skin conditions including peculiarities in special groups (e.g. men, children, ethnic diversity);
• – Classification and types of wrinkles;
• – Aspects of special body locations;
• – Awareness of the correct indications for topical preparations, medical treatment, tissue augmentation, botulinum toxin, peeling, laser treatment, surgical procedures and others
• – Judgment in handling of unwanted effects of cosmetic treatments;
• – Social, psychological and psychiatric aspects of cosmetic dermatology including knowledge about body dysmorphic disorder;
• – National and international legal aspects and regulations concerning all aspects of cosmetic dermatology.

The above-mentioned four practical areas of activity in cosmetic dermatology are as follows:

Biophysical, non-invasive, in vivo measurements of skin physiology

• – Standardized photography;
• – Measurement of skin hydration (Corneometer);
• – Measurement of transepidermal water loss (Evaporimeter);
• – Measurement of skin surface lipids (Sebumeter);
• – Measurement of skin surface pH (pH meter);
• – Measurement of elastic properties of the skin (Cutometer);
• – Evaluation of skin surface morphology (Visioscan);
• – Objectivation of skin color (Chromameter);
• – Measurement of skin thickness and density (20 MHz Ultrasound).

Topical preparations (Dermocosmetics)

• – Maintenance of healthy skin/individual skin care guidance;
• – UV-protection measures;
• – Supportive treatment of patients with skin diseases;
• – Treatment and prevention of skin ageing and other cosmetic disorders;
• – Decorative cosmetics/camouflage cosmetics.

Many cosmetic dermatologists advise patients with healthy skin how to maintain their healthy, youthful appearance. They try to develop an optimal skin care regimen for each patient to avoid problems caused by the usage of non-ideal cosmetic products. Skin care products should always be adjusted to the individual’s skin type and skin condition, e.g. lipid-rich creams or ointment formulations for dry skin and water-rich oil-in-water-(O/W) emulsions for greasy skin.

At the same time many patients are asking for recommendations on how to prevent or reverse clinical signs of ageing with topical formulations. Both the base preparation and the optimal choice of active ingredients are important. A dermatologist with specialized knowledge can recommend products containing ingredients with scientifically evaluated efficacy. Substances with demonstrated effects on collagen metabolism include retinol, vitamin C and E, co-enzyme Q10, copper tripeptide and isoflavones. Apart from skin ageing, there are a variety of other cosmetic disorders, which can be treated with topical products, such as preparations containing depigmenting agents for melasma.

Dermocosmetics are used not only for maintaining healthy skin and treatment of cosmetic disorders, but also for supportive measures in selected skin diseases such as acne, ichthyosis and atopic dermatitis. Emollients are valuable for atopic eczema, both in acute flares and in non-symptomatic periods to avoid or delay relapses. Camouflage cosmetics and decorative products may also be used for patients with disfiguring skin diseases such as acne, rosacea or port wine stains, where they have been shown to significantly improve quality of life.

Cosmetic dermatology with topical preparations also includes efficient and safe protection of the skin against ultraviolet (UV) rays, as some cosmetic skin disorders such as melasma and premature skin ageing are largely caused or made worse by UV-light.

Important aspects of theoretical knowledge obligatory for dermatologists working with topical dermocosmetics are:

• – Understanding of galenic formulations and base preparations;
• – Pharmacology of cosmetic products including percutaneous absorption, penetration and diffusion of ingredients and their implications for safety and efficacy;
• – Knowledge about ingredients and their mechanisms of action in:
  • • skin care products,
  • • skin cleansing products, masks and astringents/toners,
  • • hair care products,
  • • nail care products,
  • • topical deodorants,
  • • camouflage cosmetics and other decorative cosmetic products,
  • • self-tanning products containing dihydroxyacetone (DHA),
  • • depigmenting agents;
• – Legal and ethic aspects.

Therapy with minimally invasive techniques

The injection of diluted botulinum toxin in an out-patient setting is a quick and relatively uncomplicated procedure. The full clinical effect is reached within ten days and stays for approximately 4-6 months. Although side effects are usually minimal, the procedure should only be performed by experienced dermatologists, as an incorrect injection might result in unwanted effects such as a (temporarily) hanging eye lid (ptosis).

Botulinum toxin can also be used to effectively treat excessive sweating (hyperhidrosis). However, hyperhidrosis is usually considered a medical, rather than cosmetic, problem.

Soft tissue augmentation with injectable fillers. Soft tissue augmentation with injectable fillers is an excellent treatment modality for patients with static wrinkles and other soft tissue defects such as atrophic scars. Another use of injectable fillers is augmentation of the lips. Today there are numerous substances with different characteristics on the market, which can be injected with or without prior administration of a local anesthetic in an outpatient setting.

Injectable filler materials can be divided into two main groups: i) permanent (non-resorbable) and ii) non-permanent (biodegradable) substances, the latter of which are resorbed after weeks, months or sometimes even more than a year depending on material and other variables (table 1). Products known as “semi-permanent” contain a permanent material (e.g. polymethylmethacrylate) and a non-permanent compound (e.g. hyaluronic acid or collagen). Each material has its specific indications, risks and side-effects (e.g. risk of allergic reaction to collagen-containing products). However, non-permanent fillers are usually more easy to control and associated with fewer unwanted effects.

Chemical peels. Chemical peels are a popular method to reduce fine wrinkles and signs of photoaging in the face, improve the overall texture of the skin, ameliorate epidermal hyperpigmentation and can be used to treat certain skin diseases such as acne. Chemical peels can be divided into four different classes depending on their depth of penetration: i) very superficial, ii) superficial, iii) medium and iv) deep (table 2). The depth of penetration is not only dependent on the substance itself, its concentration and administration time, but also on various other factors such as pH of the solution, buffer, vehicle, application technique (e.g. occlusion, massage), skin condition (e.g. impairment of the epidermal barrier function, dry skin versus greasy skin), location, pre-treatment, repetition of application, and interval between treatment sessions. The deeper the penetration of the peel, the higher the risk of unwanted effects such as infection of the peeled area and scar formation. Deep peels also need to be carried out under full anesthesia and with close follow-up. The benefit of deeper peels is that they allow more impressive and pronounced clinical effects to be achieved. Very superficial and superficial peels, in contrast, produce less profound results, but can be performed readily in an out-patient setting (“lunch-break peels”).
Table 1 Selection of injectable substances for soft tissue augmentation

Miscellaneous

• – Scars and keloids;
• – Certain pigmentary disorders;
• – Disorders of the nails;
• – Disorders of the hair including hair removal techniques;
• – Striae distensae and cellulite.

Requirements and infrastructure

Achievements and limitations

At present, however, there is obviously the need for a better definition of competence in cosmetic medicine in most countries in Europe, as it is performed not only by dermatologists, but also a variety of other medical specialties. Yet, in order to maintain and extend the high standard and integrity of cosmetic dermatology, it is important to keep the main aspects of this skin-oriented area an established part of the practice of dermatologists.

Optimal understanding of the physiology and pathophysiology of the skin and its appendices, expertise in galenic prescription practice and knowledge in evaluating topical preparations as well as skin physiology are indispensable requirements for the development and preservation of safe and scientifically grounded cosmetic medicine. It is vital that topical preparations with systematically proven efficacy and evaluated safety are separated from cosmetic products without confirmed benefits. Thus, cosmetic medicine is in good hands with specialized dermatologists.

Future prospects

• a) Increase high quality basic and clinical research in all aspects of cosmetic dermatology.
• b) Define a curriculum for sub-specialty training in cosmetic dermatology.
• c) Identify training centers and establish regulations for accreditation of training programs.
• d) Certify a Board of Examination for special qualification in Cosmetic Dermatology.

Summary

Suggested reading

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9 Said S, Meshkinpour A, Carruthers A, et al. Botulinum toxin A: its expanding role in dermatology and esthetics. Am J Clin Dermatol 2003; 4: 609-916.

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11 Varani J, Warner RL, Gharaee-Kermani M, et al. Vitamin A antagonizes decreased cell growth and elevated collagen-degrading matrix metalloproteinases and stimulates collagen accumulation in naturally aged human skin. J Invest Dermatol 2000; 114: 480-6.

12 Vermeer BJ, Gilchrest BA. Cosmeceuticals. A proposal for rational definition, evaluation, and regulation. Arch Dermatol 1996; 132: 337-40.

13 Williams SC, Kimmig W, Moll I, et al. Cosmetic dermatology in German dermatology departments – Outcome of a national survey. JDDG 2003; 1: 910-4.