In the world of injectables, brand names like Juvéderm and Restylane have become synonymous with hyaluronic fillers known to smooth, plump and reshape areas where there’s a volume deficit. However, the most recent filler brand to launch in the U.S., Revance Theraputics, has also made a name for itself for its collection of RHA fillers and its most recent launch, RHA Redensity for the treatment of lip lines. Here, everything you need to know about RHA 2, 3, 4 and Redensity.

What are some unique characteristics of the RHA 2, RHA 3 and RHA 4 family of fillers?

Boca Raton, FL oculoplastic surgeon Steven Fagien, MD notes that these interesting and exciting new options in the hyaluronic filler market have a uniqueness that has some distinct advantages. “These are excellent HA fillers for blending and contouring the face without over-volumization for those that desire rejuvenation and enhancement without the need or desire for obvious projection,” he explains. “They work well to ‘blend’ facial fine lines with dermal and sub-dermal precision placement.”

Which RHA filler works best for different areas of the face? 

Santa Monica, CA dermatologist Ava Shamban, MD notes that the main difference between each RHA filler is the amount of crosslinking between them. “RHA 2 is best for perioral lines and can also be used for the radial cheek lines and in higher levels of the dermis for a more surface level smoothing.”

“One of the best under-eye fillers is RHA 2,” says New York dermatologist Julie Russak, MD. “It is approved in Europe for the under eyes, which has shown to have great success.”

“RHA 3 can be used for nasolabial folds and the commissures, or the corners of the mouth,” adds Dr. Shamban. “RHA 4 is best for deeper nasolabial folds and for deeper lines in the lower face and jawline. It’s also been used off-label in the midface to contour the cheeks.”

How does RHA Redensity help enhance and rejuvenate the mouth?

The latest hylauronic acid filler to join the Revance family is Redensity, a new FDA-approved lip line injectable treatment. “Redensity has the potential to be a game changer for the mouth region because large clinical trials suggest it integrates beautifully with the skin while lasting up to 52 weeks,” notes San Francisco dermatologist Amelia Hausauer, MD. “This means those barcode lines are gently faded out for a more smooth skin appearance that persists.”

“RHA Redensity is the only filler designed for the finest wrinkles and lines around the lips—kiss or smoker’s lines—and smile lines,” says Davie, FL dermatologist Marianna Blyumin-Karasik, MD. “It’s ideal for dynamic areas, it’s very natural looking and adaptable, and it lasts about one year.”

How does crosslinking make the RHA collection of fillers distinctive?

According to Dr. Shamban, free hyaluronic acid present in skin care, as well as our native HA, breaks down rapidly and is metabolized in about 48 hours. To prevent this happening to HA fillers injected into the skin, these HA chains are crosslinked with chemical proteins that are suspended. “There are fewer chemical proteins, less modifications and additional processes required in the manufacturing process. This yields a purer and ultimately cleaner product,” she explains.

“The difference between RHA and first-generation hyaluronic dermal fillers on the market is the fewer chemical modifications and crosslinking in longer chains of HA. Therefore, the RHA product most closely resembles native product in our body for both flexibility in usage, natural results and longevity. This is what makes them undetectable regardless of facial movements and as I always say—we only want to see results, not the product.”