Hyaluronic acids (HAs), which were first approved by the FDA for use in soft tissue augmentation in 2004, have proven to be the temporary fillers of choice for lips when used by skilled and properly trained injectors. HA fillers can last 1 year and, in some cases, longer. They are biologically pure with low protein loads. Commonly used nonanimal stabilized HA gel agents include the Juvéderm family (Allergan, Irvine, California) and Restylane and Perlane (Medicis, Scottsdale, Arizona). These agents are approved by the FDA for soft-tissue augmentation, but presently no HA is approved for use in the lips, although this is one of the most common off-label uses of these agents. HAs are both biocompatible and biodegradable, and the lack of animal proteins provides increased purity and eliminates the need for skin testing. When compared with bovine-derived collagen, they offer much greater longevity, and they provide a natural and aesthetically pleasing result with minimal adverse events.
Perhaps the most common side effect of HAs is swelling, which, through application of ice, generally subsides within hours. Lumpiness can also result, especially in the hands of inexperienced or untrained injectors; however, this can be effectively managed with the injection of a very small quantity of hyaluronidase to dissolve the unwanted accumulation of HA.
In recent years, we have seen an explosion of filling agents available for soft tissue augmentation, including the use of permanent filling agents. However, it is my strong opinion that permanent and so-called semi-permanent fillers can cause permanent problems. As previously noted, no filler is approved by the FDA for use in the lips, and although off-label use is commonplace, some substances should never be used in the lips. The manufacturer of calcium hydroxylapatite (Radiesse, BioForm Medical, San Mateo, California), which is approved by the FDA for the correction of moderate to severe facial wrinkles and folds such as nasolabial folds and the correction of lipoatrophy in people with HIV, specifically warns against the use of this agent in the lips. We have seen disastrous results with this filler when used in the lips and similar adverse events with the use of polymethylmethacrylate (PMMA) and poly-L-lactic acid in the lips, which is currently approved only for use in HIV facial lipoatrophy. In general, when the face changes as the result of aging, certain gravitational changes take place in everyone, and when permanent agents are injected, they do not change or age with the face naturally over time, which can create a very distorted appearance. Furthermore, many of these permanent substances have long-term adverse events; some, such as PMMA, have had foreign body granulomas reported many years after implant. I therefore believe that for purely cosmetic lip augmentation, these agents should be avoided.
Minimally invasive lip augmentation using temporary injectable fillers can dramatically improve aesthetic appearance. When done by a properly trained injector, there are minimal side effects and virtually no down time. Lip augmentation properly done allows patients to look younger, natural, and attractive.
