If it seems like there are a million different sheet masks on the market, you're probably right. There are masks for fighting everything from breakouts to aging skin to hyperpigmentation. They're made of all sorts of materials including cotton, hydrogel and even kelp. Some are basic and some are seriously Instagram-worthy. But the one thing most masks have in common is that they're saturated with serum or essence. After all, packages often boast words like "dripping," "drenched" and "soaked" in a whole bottle of serum.

Turns out, that doesn't apply to every sheet mask. The new breed of dry sheet masks don't prescribe to the "wetter is better" philosophy. If you're wondering how a sheet mask actually works without its characteristic liquid serum, we turned to the experts to find out what the deal is with dry sheet masks.

Image via Nannette de Gaspe

A dry sheet mask consists of a fabric mask sheet infused with a waterless, emollient, moisturizing formula, explains Jude Chao, blogger at fiddysnails and marketing director at Beautytap. Some might say that the more accurate term would be "waterless masks" but dry is still appropriate because the sheet masks actually do feel dry to the touch — unlike traditional sheet masks which are literally dripping in serum.

What's interesting is that it's not Korea that's dominating the dry mask scene. Montreal-based Nannette de Gaspe is the pioneer in the area. The brand's Youth Restoring Techstile Treatments are dubbed the world's first waterless sheet mask and they come in versions for the face and body. The brand recently launched its more affordable dry sheet mask sister brand Miss de Gaspe. Charlotte Tilbury also has its Instant Magic Facial Dry Sheet Mask, $27.

Image via Charlotte Tilbury

Trying to figure out how skin actually reaps the benefits of a dry sheet mask? The moisturizing formula in dry sheet masks is softened and released onto skin via the wearer's body heat and/or by massaging the mask while it is worn, says Chao. Once the formula is deposited onto skin, it acts like any facial moisturizer. The emollient-rich formula will smooth the surface of skin by filling in gaps of the skin barrier, creating a protective layer against moisture loss.

Nannette de Gaspe Beaubien says that her brand's dry sheet masks — or "infusers" — use Biomimetic Micro Vectors (BMV) transport technology which allows for micro penetration of active ingredients through multiple layers of the dermis. Without getting too science-y, the active-rich BMV has a balm-like texture which is imprinted on the brand's techstile infusers. When the infuser is applied, temperature, pH and/or natural body movements activate it. The BMV technology has components similar to skin's composition so when they come in contact with each other, the two seamlessly merge. Beaubien points out that instead of just filling the lipids, the high concentration of actives in the formula repairs cells.

Image via Miss de Gaspe

Application

Dry sheet masks are applied in a similar manner as traditional wet versions. After cleansing and toning, apply the mask to your face. The Nannette de Gaspe, Miss de Gaspe and Charlotte Tilbury masks all have ear straps for a secure fit. Like most other sheet masks, they're meant to be left on for about 15 minutes. The difference is, most dry sheet mask instructions encourage you to massage the mask while wearing it for maximum absorption.

Reusing dry sheet masks

Dry sheet masks can actually be reused without compromising hygiene. For instance, the Charlotte Tilbury dry mask instructions state that it can be worn three times. Similarly, the Nannette de Gaspe products are reusable for about three to five applications, depending on the condition of skin. Beaubien explains that after each application, users just have to ensure they keep the infuser dry and seal it up in the hygienic pouch to prevent it from drying out.

Image via Miss de Gaspe

Though Beaubien says that Nannette de Gaspe masks are suitable for all skin types, Chao cautions that some dry sheet mask formulas might not be ideal for everyone. She warns that the heavier formulas might be problematic for those with oily or blemish-prone skin. What's more, some users have stated dry sheet masks can leave behind an oily residue, which feels unpleasant on oily skin.

Those with dehydrated skin might find that dry sheet mask formulas lack the humectant-rich, watery moisturizer they need. Those with sensitive skin should also be careful as some dry mask reviewers have complained about redness and irritation.

Image via @missdegaspe