Many times these terms are used incorrectly by clinicians, and it is important to understand the difference.
Superficial frosting is a crystal residue of salicylic acid that accumulates on the surface of the skin and can be wiped away. Although it is very fine in texture, these crystals can be seen when using Jessner’s solutions, the PCA Peel® formulas and solutions containing salicylic acid. Many times the crystals are so fine they are barely visible to the naked eye, but they will fluoresce under a Wood’s Lamp, which makes it helpful to check for even application of the peel formulation.
Protein coagulation, also referred to as blanching usually occurs from deeper peeling, such as medium depth or deeper. A full-face blanch may be performed by physicians to treat deep wrinkling or scarring, but should not be performed by skin care clinicians who are not physicians or working under the advisement of a physician. Blanching of this nature will result in open skin and a physician-recommended occlusive lubricant should be applied to keep the area protected and moist.
On occasion, spot-blanching may occur when any peel has penetrated more deeply in areas where the skin is more sensitive (a patient may forget to inform the clinician of a recent waxing) or where an extraction was performed. This area will appear very red initially, and then appear white. This cannot be wiped off, as with frosting, and may or may not cause discomfort to the patient. Advise the patient that they may peel more and will probably have some darkening at the blanch site, and to keep the area hydrated, use SPF and do not pick or pull at any exfoliating skin.
Keep in mind that if a patient’s peel penetrates deeper in specific areas, those areas will have a pH closer to blood (7.3-7.4) than intact skin (5.5). Products must be chosen carefully to accommodate for this change in pH. Once the area is re-epithelialized (approximately 48 hours) the patient may introduce Hydrating Serum and Silkcoat Balm®. To create an environment that can effectively produce natural moisturizing factor (NMF). Patients who experience minor surface blanching may continue using the PCA SKIN® Post-Procedure Solution.
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Isn’t Level 3 Frosting also blanching?
Level 3 frosting would be considered a deep peel. The terms tend to be used interchangeably by some, however frosting is associated with salicylic acid crystals that can be removed from the skin; whereas blanching is deep, not superficial, and cannot be removed.