Cosmetic Fillers and Wrinkles

Medically Reviewed by Stephanie S. Gardner, MD on July 26, 2021
3 min read

Cosmetic fillers are materials injected underneath the skin to make it fuller. After an injection, the plumper skin shows fewer wrinkles and looks younger.

Injectable cosmetic fillers have been around for decades. In recent years, medical advances have brought new versions of this wrinkle treatment to the marketplace. Newer cosmetic fillers are longer lasting, even semi permanent. But be sure to do your homework before heading to the cosmetic surgeon.


Skin is held tight and smooth by three critical components: collagen, hyaluronic acid, and elastin. These chemicals combine to create a firm, spongy meshwork under the skin surface. This elastic structure keeps the skin surface smooth and firm.

With age, this meshwork slowly loses its integrity. With weakness in the underlying support structure, the skin's surface loses its perfect baby-skin smoothness.

Injecting cosmetic fillers helps fill the thinned-out meshwork. The fillers plump up the tissue underneath the skin, shrinking wrinkles. The skin becomes firmer, smoother, and younger-looking.

Collagen is the oldest and best-known cosmetic filler. Newer natural and synthetic products are available, each with their own advantages and disadvantages.

Bovine collagen is processed from the skin of cows. Approved in the 1980s as a wrinkle treatment, bovine collagen is still widely used as a cosmetic filler.

Bovine collagen is effective and less expensive than other treatments. It can cause allergic reactions, so allergy skin testing is generally done before beginning the injections.

The body naturally breaks down injected collagen, so you need to get collagen injections two to four times per year to maintain results.


Human collagen, made from cultures of human cells, became available in 2002. Human collagen causes dramatically fewer allergic reactions than bovine collagen, so skin testing is not needed. It is more expensive than bovine collagen, and injections also need to be repeated every three to six months.

Hyaluronic acid is a natural part of skin. With age, you have less of it in your skin.

Various natural and synthetic hyaluronic acid (HA) products are available. In the newest products, the HA molecule is modified to break down more slowly. Cosmetic results can last nine months or longer. Allergic reactions are very rare.


Ever wish you could move that fat from your thighs to somewhere it might look a little better? Fat injections involve removing small amounts of fat from the thighs, belly, or buttocks and injecting it under the skin of the face. The fat expands the skin, shrinking wrinkles. Because it is your own tissue, there can be no allergic reaction. Results vary and sometimes last a long time.

When injected under the skin, poly-L lactic acid (PLLA) stimulates skin cells to make collagen. Poly-L lactic acid is nontoxic and has been widely used in suture material for years.

PLLA is FDA-approved for cosmetic treatment of certain skin conditions in people with HIV. It is often legally used "off-label" to treat wrinkles in otherwise healthy people. It's considered "semi-permanent," meaning results can last for months to years.


In 2006, the FDA approved calcium hydroxylapatite for cosmetic injection. This cosmetic filler is made of the minerals that give bone its strength and texture. These minerals are ground into tiny particles and suspended in water solution, which is injected under the skin.

In the trial that led to its approval, calcium hydroxyapatite worked significantly better and lasted longer than collagen injections to reduce severe wrinkles.


Polymethyl methacrylate is a semi-permanent cosmetic filler. Before the FDA approved it for that use, PMMA was already being used as a cement for bone surgery.

That's right -- we said "cement." Polymethyl methacrylate doesn't readily break down. So, unlike biological products, PMMA produces semi-permanent cosmetic results.