Fillers, also known as injectable implants, dermal fillers, or wrinkle fillers are medical device implants approved by the Food and Drug Administration (FDA) for use in helping to create a smoother and/or fuller appearance in the face, including nasolabial folds, cheeks and lips and for increasing the volume of the back of the hand.

Before delving into a discussion about dermal fillers, it is important to make one point: Dermal fillers, such as those listed above, are often confused with wrinkle relaxers, such as Botox and Dysport. While dermal fillers and wrinkle relaxers are both considered “injectables,” they are in two entirely different categories. Botox and Dysport are used to paralyze muscles and stop the motion of muscles that cause wrinkles. They are not used to fill, plump, or enhance an area. They can however be used in conjunction with fillers.

Dermal fillers can be used to plump thinning lips, give the eyebrows a bit of a lift, enhance cheek bones, decrease hollowing under the eye to help reduce dark circles, decrease the appearance of smile lines and overall just give you a well-rested and rejuvenated appearance. They can be done in less than an hour and have little to no downtime.

In some people, dermal fillers may cause some mild bruising, temporary swelling, or temporary redness at the injection site. Rarely, a person might experience an allergic reaction. The major disadvantage of dermal fillers is the effects are indeed temporary. There is one exception to that, though, which will be addressed. For the most part, however, the effects can last from a few months up to a year and a half.

Most dermal fillers have a temporary effect, because they contain materials that are absorbed by the body over time. The FDA has approved only one product made from a material that remains in the body and is not absorbed. Some soft tissue fillers also contain lidocaine, which is intended to decrease pain or discomfort related to the injection.

Below are materials and a brief run-down of their uses and how they work:

Absorbable (temporary) materials:

  1. Collagen:Collagen is a type of protein that is a major part of skin and other tissues in the body. Sources of purified collagen used in soft tissue fillers can be from cow (bovine), pig (porcine) or human cells. The effects of collagen fillers generally last for 3-4 months. They are the shortest lasting of injectable filler materials.
  1. Hyaluronic acid:Hyaluronic acid is a type of sugar (polysaccharide) that is present in body tissues, such as in skin and cartilage. It is able to combine with water and swell when in gel form, causing a smoothing/filling effect. Sources of hyaluronic acid used in dermal fillers can be from bacteria or rooster combs (avian). In some cases, hyaluronic acid used in dermal fillers is chemically modified (crosslinked) to make it last longer in the body. The effects of this material last approximately 6 – 12 months.
  1. Calcium hydroxylapatite:Calcium hydroxylapatite is a type of mineral that is commonly found in human teeth and bones. For wrinkle filling in the face or in the hand, calcium hydroxylapatite particles are suspended in a gel-like solution and then injected into the wrinkle in the face or under the skin in the back of the hand. The effects of this material last approximately 18 months. While in the body, calcium hydroxylapatite will be visible in x-rays and may obscure underlying features.
  1. Poly-L-lactic acid (PLLA):PLLA is a biodegradable, biocompatible man-made polymer. This material has wide uses in absorbable stitches and bone screws. PLLA is a long lasting filler material that is given in a series of injections over a period of several months. The effects of PLLA generally become increasingly apparent over time (over a period of several weeks) and its effects may last up to 2 years.
  1. Fat Fillers (Fat grafting): There is no question that fat is the ideal material for soft tissue augmentation, and that the results obtained with fat grafting are the most natural-appearing, when performed by a plastic surgeon with expertise using the ideal instrumentation.

However, one problem with this procedure in years past has been resorption (breakdown) of the grafted fat, so that the resulting improvement is not permanent. The grafted fat must gain its own blood supply in its new location in order to persist long-term, and this generally is not possible when large amounts are injected at once and when specialized instrumentation and techniques are not employed. A relatively new technique has been developed called structural fat grafting, in which small amounts (less than 0.1 cc at a time) of fat are carefully microinjected in a series of discrete layers to gradually ‘build’ new soft tissue structure.

As there is space between each microinjection, new blood vessels are able to grow into the grafted fat, allowing it to persist. If this process of blood vessel ingrowth (neovascularization) does not occur, then the injected tissue cannot truly be considered a ‘graft’ and is instead just another ‘soft tissue filler’ of limited duration. This is a procedure that requires specialized training and specialized surgical instruments, as well as patience and attention to detail on the part of the surgeon. When performed properly, permanent improvements in facial plastic surgery are possible.

If enough fat resorption occurs following a fat grafting procedure such that the desired result is not achieved, a second ‘touch-up’ procedure can easily be performed to augment the result obtained from the first injection.

Non-absorbable (permanent) materials:

  1. Polymethylmethacrylate beads (PMMA microspheres): PMMA is a non-biodegradable, biocompatible, man-made polymer. This material is used in other medical devices, such as bone cement and intraocular lenses. PMMA beads are tiny, round, smooth particles that are not absorbed by the body. When used as a soft tissue filler, PMMA beads are suspended in a gel-like solution that contains cow (bovine) collagen and injected into the face.

Finding the right dermal filler for you will depend on your budget, your doctor’s experience and preference, and your individual skin nuances (e.g. amount of sun damage, skin elasticity) and facial features. What works for your friend may not be the best option for you. It is best to select a dermal filler type on a case-by-case basis.