Non-Resorbable Filling Substances
Liquid silicone varies by degree of purity, and the form that is being used in the US is sterile, purified, medical injectable grade silicone. The newest method of injection is referred to as the “micro droplet” technique, which has the advantage of causing fewer hard lumps than previous variations. Liquid silicone is only approved by the FDA for ophthalmic uses, so cosmetic uses are considered an off label use of an approved product.
Fat is perhaps the most widespread material used as a filling substance in facial rejuvenation. The fat that is injected into facial areas comes from your own body, so there is no chance of an allergic reaction or “rejection”. Fat can be used in higher volumes than most other injectable materials and can be used to create a fuller, more youthful appearance by reestablishing pleasing contours. Injections of fat into the deep layers of facial tissue can soften the angular, thin appearance that often accompanies aging. Fat is the first choice of material when injections of volumes greater than 10cc are needed.
The fat must be harvested from your own body, typically from the abdomen, thighs or hips. After it is extracted, it is placed in a centrifuge to separate the fat from blood and other fluid. The fat is then packed into a syringe ready to be injected. Because fat molecules are somewhat larger than other injectable materials, it is usually injected more deeply and with a larger gauge needle. Volumes of up to 50 -100 cc’s can be injected at one stage. Fat injections are particularly useful in the lips and perioral area, in cheek hollows and around the eyes, as well as for some scars.
“Fat is one of the most commonly used fillers for plumping-up deep folds and restoring youthful contours”
Fat injections have a very variable life span. The fat is slowly absorbed by the body, although the amount of absorption is variable, and hard to predict. Typically, more than half of the fat used in injectable treatments is absorbed with six months of the procedure, although it may last longer. Almost all people will permanently retain some of the injected fat. Two to three follow up treatments are usually advised and can lead to a more permanent correction.