Here's how they work

dermal fillersWrinkle fillers can be divided into two categories: Temporary and Semi-Permanent.

Temporary

Human fat, also known as autologous fat, is harvested from your own body. Using your own fat requires a more extensive procedure than other injectable fillers because you first must undergo liposuction to extract the fat prior to injection. You eliminate the risk of allergic reaction or rejection by the body by using your own fat. You should know that not all of the live fat cells survive when transplanted into a new site. You can expect a fairly high rate of re-absorption. Because of this, your doctor will likely overfill the area being treated. At first you might look abnormal, but it will soon settle and you'll enjoy a new look. When your doctor extracts this fat via liposuction, it's possible that there will be more than is needed for one application. Most natural fat can be stored for touch-ups.

Collagen is a natural substance known as a protein, and the main component in cartilage, teeth and bones. It is derived either from human skin or cows (known as bovine collagen). Brand names include: CosmoDerm, Cosmoplast, Zyderm, Zyplast.

Human cadaveric dermis is skin that's cultivated from a cadaver, then injected into your face. This substance results in particularly impressive filling of facial hollows. Brand names include: Cymetra, Dermalogen, Fascian.

Hyaluronic acid is also a natural substance found in your body. High concentrations are found in soft connective tissue and in the fluid surrounding your eyes. It's also in some cartilage and joint fluids, as well as skin tissue. If the name sounds familiar, it's because the same substance is often injected into the aching joints of people with arthritis to ease pain by providing extra cushioning. Hyaluronic acid is not derived from animal sources. Brand names include: Captique, Esthélis, Elevess, Hylaform, Juvéderm, Perlane, Prevelle, Puragen and Restylane.

Calcium hydroxylapatite, the heaviest of facial fillers, is found naturally in human bones. This mineral-like compound is reserved to fill the deepest creases such as nasolabial folds, marionette lines and frown lines. It's also used to enhance fullness of the cheeks and other facial contours. Calcium-based microspheres are suspended in a water-based gel. Brand names include: Radiesse, Radiance.

Polylactic acid is a synthetic material. When it is injected, it stimulates the body's own production of collagen. This substance is known to work particularly well in the lower half of your face to fill the lines caused by laughing, to augment thin lips and fill out deep nasolabial folds. This substance is unlike other dermal fillers because it doesn't produce immediate results. Instead, it stimulates collagen production, so results appear gradually over a period of a few months. Brand names include: Sculptra, New-Fill.

Semi-Permanent

PMMA (polymethylmethacrylate) fillers contain about 20 percent of tiny PMMA microspheres that are suspended in 80 percent purified collagen gel. This substance, considered semi-permanent, can be removed. PMMA is most often used to treat medium-to-deep wrinkles, folds and furrows, particularly nasolabial folds. It can also be used to fill out pitted scars and to augment thin lips. PMMA has been used for many years in permanent surgical implants. Because of this, your surgeon will likely under-fill on the first treatment, adding more later if needed. Brand names include: Articol, Artefill, Metacrill.