Remember that one time someone cut open a BeautyBlender makeup sponge, and the horrifying (and moldy) results went viral? Sorry for unearthing repressed memories, but there's a lesson to be learned from the putrid state of the product: Like cosmetics products, makeup sponges have expiration dates — and they shouldn't be ignored.

Which is why it's so damn important to wash — and eventually replace — the tools (i.e. BeautyBlenders, sponges, wedges, etc.) you use to paint on your daily face beat regularly, says Ava Shamban, a Beverly Hills-based dermatologist. "For blenders and sponges, you should wash regularly and replace every three months," she says. "If they're really wet and smelly, they can be placed in the washing machine."

Ideally though, we should be cleansing our tools after every use to avoid bacteria buildup (ewwwwww), adds Shamban. "The sponges become filled with skin cells and bacteria can overgrow in that area." And that overgrowth — if unnoticed — can irritate skin and blemishes, if you have them. "If there are any potential allergens remaining in the sponge after makeup application, then it's conceivable that repeated contact could lead to an inflammatory rash."

Of course, you could avoid the overgrowth risk completely by skimping on a sponge altogether, but that's not realistic. What is, though, is celebrity makeup artist Molly Stern's technique, which is to skip the sponge and instead use disposable wedges to seamlessly apply your makeup. "I'm not a fan of the BeautyBlender, personally, because I feel like you can't ever really get a sponge clean — like bacteria-free clean," she says. Makes sense, considering Stern works with the faces of Hollywood's elite on the daily.

"For me, professionally, it's not an option, so I use high-quality deluxe wedge sponges, which are super-smooth and super disposable," Stern tells Allure. "I prefer a disposable [wedge] used a few times." Our pick? The Best of Beauty-winning

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Essence of Beauty Makeup Wedges

These latex-free makeup sponges spread and blend foundation, tinted moisturizer, and cream blush.

, which fit into tight corners and crevices and leave behind a flawless finish. Bottom line: No matter what side of the makeup sponge debate you fall on, please keep them (and whatever other tools you use every day) clean.

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  2. Artis Brush Is Offering Its Luxury Makeup Brushes at a HUGE Discount Right Now
  3. Primark Just Dropped a Set of FIVE Unicorn Makeup Brushes for $10

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