Understanding the skin, our largest organ, is crucial for any Medical Aesthetics professional, especially when it comes to developing a skincare treatment plan that is customized for their patient’s issues.

In this module, we examine the science of skin and review some of the more well-known topical, noninvasive treatments used to address dermatological skincare concerns

How is the skin structured?

Overall, the skin functions in many capacities including protection, prevention of water loss, and a role in thermoregulation.¹ But beneath the continuous surface, there are three main layers of skin, and even within each layer there are sublayers, each with its own role.

Source: National Cancer Institute

• Epidermis

  This is the outermost layer of the skin and protects the body from the environment and contains our sensory nerves.
  • This layer itself is made of five sublayers that collectively work to rebuild the surface of the skin:

• Basal Cell Layer

  Innermost layer of the epidermis that continuously produces new cells. This layer also includes melanocytes, which produce melanin, which gives the skin its brown color and also protects the skin from the sun’s UV radiation.²

• Squamous Cell Layer

  Located above the basal layer, it is the thickest layer on the epidermis that produces keratinocytes, which in turn create keratin (a tough protein that makes up skin, hair, and nails).³

• Stratum Granulosum and the Stratum Lucidum

  Keratinocytes go through these two layers and become larger and flatter and begin to stick together until they become dehydrated and die. These dead cells fuse into a tough layer which go onto the stratum corneum.

• Stratum Corneum

  This is the outermost layer of the epidermis and is where the cell turnover process takes place. Complete cell turnover occurs every 28 to 30 days in young adults, and 45 to 50 days in elderly adults. 

• Dermis

  This is the thickest of the three layers—making up approximately 90 percent of the thickness of the skin and giving the skin its plumpness.⁴ This layer contains the blood vessels, lymph vessels, hair follicles, sweat glands, sebaceous glands and nerve endings, collagen, and elastin. The dermis is further made of two layers:

  • Papillary Layer

    Provides nutrients to the epidermis and also assists with thermoregulation³

  • Reticular layer

    Thicker, inner layer (below Papillary) and assists with providing both structure and elasticity⁴

• Subcutis

  Innermost layer that consists of fat and collagen cells and serves as an insulator and shock absorber. Thickness of this layer varies from person to person, but overall, a decrease of tissue in this layer leads to sagging skin.⁴

• Additional Skin materials/proteins to be aware of

  Collagen and Elastin are proteins responsible for giving structure to the skin; however, over time the body reduces the amount it is able to produce,⁴ leading to less firm skin for more mature patients

What are current topical skincare treatment types?

Dermal changes to the skin are due to intrinsic (hormonal/biochemical) and extrinsic factors (UV radiation, environment) that cause damage and fundamental changes.⁴ The great news is that Medical Aesthetics professionals can assist in addressing the age-related changes in skin quality and appearance. Here are some of the most commonly recommended topical skincare treatments:  

• Photoprotection

  Daily sunscreen applications can reduce appearance of fine wrinkles and help prevent dyspigmentation.⁴

• Retinoid therapy

  Retinoid treatment is used to improve fine lines/winkles, hyper/hypopigmentation, and facial liver spots.⁴

• Topical Antioxidants

  Help reduce skin damage from UV radiation and free radicals. Common treatments include Vitamin C and ferulic acid among others.⁴