The rising popularity of non-hyaluronic acid fillers: What you should know about these biostimulators

If you are in the market for a plumper pout or want to add more oomph to areas that are losing a little volume, chances are you are familiar with the perennially popular hyaluronic acid (HA) injectable fillers. HA fillers have been a long-time favorite to add fullness to facial features that need a little boost. Adding volume in specific facial areas can help create a youthful and more radiant appearance.

While HA fillers are unlikely to be dethroned as one of America's favorite minimally invasive treatment options anytime soon, another type of filler is gaining traction. According to the 2024 ASPS Plastic Surgery Statistics Report, new data reveals a steady year-over-year demand for non-hyaluronic acid (HA) fillers. What are non-HA fillers, and do they offer different outcomes or benefits for patients? Here's what you should know about the rising popularity of non-HA fillers.

What are non-hyaluronic acid fillers?

Hyaluronic acid is the most common injectable filler in the United States. It is found in products like Juvéderm and Restylane and is a naturally occurring compound in almost all living creatures. Yes, humans, too. Hyaluronic acid is renowned for its incredible ability to retain significant moisture. It can enhance the face and lips by adding volume and reducing the appearance of fine lines, offering an overall fresh and youthful aesthetic.

Like the name implies, non-HA fillers do not contain hyaluronic acid.

"Non-HA fillers on the U.S. market are composed of different products generally classed as 'biostimulants' and 'structural fillers,'" said Sara Dickie, MD. "These products produce a localized, controlled, inflammatory response that builds collagen over time. It's using one's own body to create the filler in a sense."

Most non-HA fillers use other substances to restore volume. Sculptra, one of the first non-HA fillers marketed in the U.S., uses poly-L-lactic acid, or PLLA. Radiesse utilizes calcium hydroxyapatite in methylcellulose gel, while Bellafil targets volume loss with polymethylmethacrylate in a collagen gel. These ingredients may not mean much to a patient, except that they possess unique properties that distinguish them from their HA filler counterparts.

What patients need to know about non-HA fillers

Non-HA fillers had some early popularity but were quickly eclipsed when HA fillers took over the market.

"The reason for this is that HA is forgiving in that it can be dissolved or reversed using hyaluronidase, and none of these others can," said Dr. Dickie.

Although non-HA fillers may be growing in popularity, there are still several advantages to the more popular HA fillers.

"HA fillers remain the most precise, customizable and safest option in the majority of aesthetic cases," said Lara Devgan, MD. "Their reversibility with hyaluronidase gives both patients and providers peace of mind, and their rheologic diversity allows us to tailor products for specific facial zones with remarkable finesse."

One of the most significant benefits of non-HA fillers is that they offer longer-lasting and sometimes more natural results than HA fillers. The big drawback is that these fillers cannot be dissolved when the results do not align with a patient's expectations.

"Radiesse and Bellafil do not have reversal agents," said Dr. Dickie. "They are gels and, if inadvertently injected into a blood vessel, can cause ischemic (reduced blood flow) damage that is very hard to treat. This is a rare occurrence, so that risk isn't the real reason people don't use them as much. But more for the fact that if patients get a nodule or a bump or lump or just an unsatisfactory result, it cannot be treated by dissolving it."

Biostimulatory benefits

While non-HA fillers may not be as popular for addressing volume loss or fine lines as HA fillers, they are a valuable tool that experienced plastic surgeons can utilize for specific purposes.

"Sculptra is best thought of as a collagen stimulator rather than a volumizer in the traditional sense," said Dr. Devgan. "It is ideal for diffuse volume correction, particularly in patients with age-related facial fat loss. It is also being used more frequently in off-face applications like buttock augmentation and cellulite improvement, where its ability to stimulate dermal thickening over time yields natural, long-lasting results."

Those are the various uses for non-HA fillers, but who are the ideal patients?

"I prefer to use it in women who are aging and generally thin," said Dr. Devgan. "It's great in Ozempic patients. Sculptra can naturally enhance the entire cheek and provide a graceful fullness that looks healthy without lumpiness or bumpiness, which can happen with HAs."

Dr. Dickie said that Radiesse has also been shown to act as a biostimulant when diluted. She likes the product for the jawline or cheeks, which Dr. Devgan echoed.

"It's thicker, more robust consistency makes it well suited for areas requiring contour and definition, such as the jawline and chin, especially in patients seeking crisp, immediate results that mimic bone or deep tissue," said Dr. Devgan.

Non-HA fillers can also be used for acne scarring since they help the body produce collagen, filling in deeper pits or pockets.

How do you know if non-HA fillers are right for you?

Dr. Devgan advocated for more patient education about non-HA fillers, what they can do and the risks associated with these products. Rare but serious side effects can occur, especially in the hands of an inexperienced or untrained injector.

Non-HA fillers may also need multiple sessions to achieve maximum results. These sessions often need to be spaced weeks apart since non-HA fillers tend to stimulate collagen production. Dr. Devgan said in her practice, she considers non-HA fillers for patients when:

• A patient is not a candidate for HA due to an allergy, overcorrection risks or prior complications
• Treating larger surface areas or structural regions where collagen stimulation or firmness is the goal
• A patient understands the commitment, time course and lack of reversibility

While non-HA fillers can complement other injectables, they may not be a replacement for HA injectables.

"Rather, they are niche solutions for specific aesthetic goals," said Dr. Devgan. "The reality is that HA fillers are still the most versatile, controlled and predictable option, especially for facial contouring, lip enhancement, tear trough correction, nonsurgical rhinoplasty and subtle refinements."

Find out which type of filler is right for you and your aesthetic concerns by consulting with a board-certified plastic surgeon who is an ASPS member.

To find a qualified plastic surgeon for any cosmetic or reconstructive procedure, consult a member of the American Society of Plastic Surgeons. All ASPS members are board certified by the American Board of Plastic Surgery, have completed an accredited plastic surgery training program, practice in accredited facilities and follow strict standards of safety and ethics. Find an ASPS member in your area.