Collagen injections and other injectable fillers give your skin a plumper, smoother appearance. Although collagen is the best known filler, there are many other substances doctors can use to plump up your skin, including fat from your own body and synthetic materials. Below you will find a detailed explanation of how collagen works, followed by a list other other injectable fillers your doctor may suggest.

Collagen

To understand collagen, you should first understand your skin.

Skin consists of three layers: the epidermis, dermis and subcutaneous tissue (hypodermis). The upper-most layer, known as the epidermis, controls the loss of water from cells and tissue. Without this protective barrier, the body would quickly dehydrate.

Just below the epidermis lies the second layer, the dermis. The dermis, although it contains blood vessels, nerves and hair follicles, is primarily made up of a protein called "collagen." This protein forms a network of fibers that provides a framework for the growth of cells and blood vessels. Because it is the primary component of the dermis, collagen acts as the support structure for the skin. The hpodermis is a layer of fat and connective tissue that contains larger blood vessels and nerves. It also hosts sweat glands, and fat and collagen cells. The hypodermis is responsible for conserving your body's heat and protecting your vital inner organs.

Why Do Lines Appear?

In young skin, the collagen framework is intact and the skin remains moisturized and elastic. It's resilient to the many facial expressions we adopt as well as everyday environmental exposure. But, over time, the support structure weakens and the skin loses its elasticity. The skin begins to lose its tone as the collagen support wears down. Every time you smile, frown or squint, you put stress on the collagen in your skin. The effect of these facial expressions is cumulative and facial lines begin to appear.

Why Aren't Creams Containing Collagen Enough to Smooth Out Lines?

Collagen creams work only on the skin surface. A moisturizer with or without collagen cannot penetrate the skin and is not designed to be absorbed. No moisturizer can undo the cumulative effect of collagen loss. Creams primarily slow the rate of water loss from the skin and help keep the skin supple.

How Do Collagen Injections Work?

Collagen injections replenish the skin's natural collagen. The natural beauty of your skin is enhanced as the contour of the support structure is restored.

Zyderm and Zyplast are bovine derived collagen products that replace the collagen your skin loses over time. Zyderm and Zyplast collagen are placed just beneath the skin, in the dermis where the body readily accepts it as its own.

CosmoDerm and CosmoPlast are bioengineered human collagen products that are used for similar indications as Zyderm and Zyplast but have the advantage of not requiring a skin test prior to the first treatment.

Collagen should be injected into your skin only by a trained health care professional. By supplementing your skin's own collagen, collagen replacement therapy helps smooth facial lines as well as most types of scars.