Hyaluronic Acid Filler vs. Biostimulatory Injectables: Which One Is Right For Me?

Despite what pharmaceutical brands hope for, when a prospective injectables patient is looking in the mirror examining his or her face, they’re thinking ‘I want to try filler’ — not ‘I need Radiesse®’ or ‘I could use 10 cc of Sculptra®.’ Plastic surgeons and cosmetic dermatologists are there to fill in the gaps, and you certainly don’t need to walk into a doctor’s office with an exact treatment plan in mind. But it can be helpful to understand the basics of two major types of dermal fillers: hyaluronic acid (HA)-based and biostimulatory.

According to John Burns, MD, a board certified plastic and reconstructive surgeon in Dallas, hyaluronic acid-based fillers are “by far” the most popular choice in his practice (and that is also true of the United States at large). He estimates that about 95 percent of his patients opt for HA, with only around five percent preferring biostimulants. But that doesn’t mean that biostimulatory injectables aren’t right for you.

Ahead, we break down the differences between HA filler and biostimulants — including a helpful guide to what to discuss with your provider.

How Hyaluronic Acid-Based Filler Works

If the term ‘hyaluronic acid’ sounds familiar, it’s for good reason. The naturally occurring humectant holds 1,000-times its weight in water and is produced by the body to lubricate the joints and moisturize the skin and eyes. When synthetic formulations of HA are applied topically via skincare, they help attract water deeper into the skin for a hydrating effect. Synthetic HA can also be injected into the skin to temporarily add volume, contour, and smooth lines and wrinkles.

Hyaluronic acid-based fillers “are biocompatible, which means it’s made with a clear, gelatinous substance that’s essentially the same sugar molecule that surrounds the cells in your body,” Dr. Burns explains. Because it is made with a substance your body recognizes, the body perceives the filler as part of itself. That means there’s less chance for a negative reaction from the tissue into which you’re injecting the filler.

There are several brands of cosmetic HA filler on the market (each with a host of sub-products that target specific aesthetic concerns), and your provider will help you determine which is best for your needs. A few of common HA fillers are:

• Juvéderm®
• Restylane®
• RHA®
• Belotero®

As for those versions we mentioned, each has different viscosities and target areas. Juvéderm®, for example, has Juvéderm® XC for lines and wrinkles, Voluma for cheek augmentation, Volbella for lips (to name a few). Restylane®, meanwhile, has Contour, Refyne, Defyne, Kysse, Lyft, Silk, which are approved by the U.S. Food and Drug Administration (FDA) to treat different parts of the face and hands. The lightweight Kysse is designed to mimic the natural feel of your lips; the stronger Lyft is used for cheeks and jawline.

Another reason HA fillers are so popular? They’re temporary and reversible. Depending on the product, treatment area, and patient’s metabolism, hyaluronic acid-based fillers generally last six to 12 months. Over that timespan, the HA naturally degrades and gets absorbed by the body. That breakdown can be sped up with an injection of hyaluronidase, an enzyme that dissolves HA. The ability to undo and/or refine results is especially helpful for patients who are new to filler, Dr. Burns says, and may be nervous about the effect.

How Biostimulatory Injectables Work

Here’s where the term ‘filler’ becomes a bit of a misnomer. “Biostimulants do some volume filling, but really their primary focus is to stimulate the collagen that’s already in your skin,” explains Esther Yoonah Kim, MD, a board certified plastic and reconstructive surgeon in southern California. The injection is designed to “produce a controlled inflammatory response” and “recruit the inflammatory cells … including those that make collagen,” she explains. That newly produced collagen is permanent.

Unlike HA-based fillers, which are absorbed into the body, the collagen created by biostimulatory injectables remains. Instead of providing an instant plumping effect, these injections stimulate the body’s own processes for longer-term smoothing and volumizing. “By their nature, biostimulants are thicker,” Dr. Kim says. As such, “they’re not good for areas that require a super soft touch,” she adds. That includes the lips and under eyes — two areas of concern for many folks coming into her office.

But that’s not to say biostimulants don’t serve a purpose. Some popular options include:

• Sculptra®: Made from poly-L-lactic acid (PLLA), a suture material used in surgical operations, Sculptra® is most commonly injected into the temples, mid-face, nasolabial folds, and areas of the body (think: knees, buttocks).
• Radiesse®: This injectable is made of calcium hydroxyapatite (CaHa), which is “a mineral-like substance that’s one of the ingredients in your bones,” Dr. Kim says. Radiesse® is often injected into areas that have become bony, like hands or cheeks.
• Bellafill®: Made from polymethylmethacrylate (PMMA) beads and cow collagen (requiring allergy testing before use), Bellafill® can be injected into depressed acne scars and nasolabial folds.

No matter what they are made of, all biostimulants have similar response-inducing properties. Generally speaking, the visible results of biostimulatory injectables last 12 to 24 months, at which point they can be touched up. So, while they require less maintenance than HA fillers, they do have a higher upfront cost per syringe and it can take six weeks or more to start seeing results.

Another key difference? Unlike HA fillers, biostimulants cannot be dissolved or reversed. Since the purpose and results of biostimulatory injectables are quite different, it is important to discuss your options with a provider who understands your desired results.

Which Injectable Is Best for Me?

Now that you know the difference between HA filler and biostimulants, you may be wondering how to determine which type is right for you. “The area of concern will dictate the conversation quite a bit,” says Kim. As we mentioned, HA fillers are best for the lips and tear troughs, but location isn’t the only factor.

If you’re new to injectables, your provider will likely recommend starting with a hyaluronic acid-based filler. “The benefit of HA is that it’s so forgiving, flexible, good for anybody, and good for almost all parts of the face,” Dr. Kim notes. It also offers immediate results, whereas biostimulant patients may not notice a change for a month or more. With that said, if you’re seeking a semi-permanent anti-aging effect on “deeper areas” like the nasolabial folds, marionette lines, or chin, biostimulatory injections may be the best choice.

As always, an open and honest consultation with a board certified provider about your aesthetic goals and concerns should be the best determinant.