Need a crash course in filler skin care 101? You're not alone. With so many options, many still wonder just what are dermal fillers and how are they used?

"Injectable dermal fillers are soft tissue and wrinkle fillers approved by FDA as medical devices. Generally, these products are injected into the skin to help fill in facial wrinkles, restoring a smoother appearance," explained Food and Drug Administration (FDA) medical officer Janette Alexander, M.D.

In addition, fat taken from other body areas is often used with the same goals. Alexander says that most of the fillers achieve a smoothing or filling effect, which lasts for about six months or longer in most people.

FDA has approved only one permanent wrinkle filler, which contains the polymethylmethacrylate beads. These are tiny round, smooth, biocompatible plastic particles that are not absorbed by the body. The filler is FDA-approved only for correcting facial tissue around the mouth.

In addition, FDA has approved a number of injectable dermal fillers that are temporary because the body eventually absorbs them. These products are used for correcting soft tissue defects in the face, such as moderate to severe facial wrinkles and skin folds, lip and cheek augmentation, and to restore or correct the signs of facial fat loss in people with human immunodeficiency virus (HIV).

You can refer to the FDA's list of approved dermal fillers for more information on a specific dermal filler.

These temporary fillers include the following materials:

- Collagen injections, made of highly purified cow or human collagen

- Hyaluronic acid gel, a protective lubricating gel, produced naturally by the body

- Calcium hydroxylapatite, a mineral and a major component of bone

- Poly-L-lactic acid (PLLA), a biodegradable, biocompatible, synthetic material 

An remember the FDA has not approved dermal fillers for increasing breast or buttock size or for injections anywhere else than the face.

And as for the risks? "As with any medical procedure, being injected with dermal fillers poses some risks," Alexander says. "You should ask what you can expect and contact your health care professional if you are concerned about a particular side effect."

Check out Part 2 of our story next week, where we talk about the possible side effects to dermal filler.