The injection of facial alines and wrinkles today is primarily done by the class of compounds known has hyaluronic acids or hyalurons. They have completely replaced the historic use of collagen as injectable skin fillers with no need for a pre-injection skin test, greater duration of action, and less incidence of potential skin complications.
The use of injectable materials for filling or plumping up facial lines and wrinkles dates back to 1981 in the U.S. when collagen injections became available. From 1981 to 2003, for over twenty years, injectable collagen was the only available facial filler. While the injection process was easy, the popularity of collagen injections was limited as its effects were very short-lived usually lasting around 6 weeks or so. Because the collagen material was bovine-derived (from cows), a skin test was required prior to injection and a small percent of patients had allergic reactions, thus not being capable of treatment. Since 2003, a new synthetic material has become commercially available and collagen is now 'a material of historic interest' primarily. This new material is hyaluron or hyaluronic acid.
Hyaluron (HA) is produced today by fermentation in cultures of equine streptococci. The fermented material is then stabilized via epoxidic cross-links of the glycosaminoglycan chains. As a result of this processing method, the HA material does not cause immunologic sensitization and virtually no risk of allergic reactions. Hyaluronan is a polysaccharide that is an essential component of the extracellular matrices in which all human tissues differentiate. In certain tissues, such as the vitreous cavity of the eye and synovial joint fluid, it is the major constituent. Unlike collagen, it is identical across all animal species and microbes. The largest amount of hyaluronan resides in skin, where it is present in both dermis and epidermis. Hyaluronan's high capacity for holding water and high viscoelasticity give it some unique properties that are useful in various medical and pharmaceutical applications.
Because it retains moisture, hyaluronan is used in some cosmetics to keep skin young and fresh-looking. As we age, the water-holding capacity of our skin decreases as hyaluronan depolymerizes. Hyaluron injected into or under the skin, therefore, helps in wrinkle reduction. HA can be rather rapidly degraded and is ultimately metabolized in the liver. Modern processing methods have produced more stable forms of HA that have much longer in vivo retention times. As degradation occurs over time, water is attracted to the material at the site of implantation. Water attaches to the HA molecules as it degrades thus accounting for its volume persistence. It is this feature which explains why it lasts longer than cow collagen. (isovolemic degradation)
A variety of differing grades of transparent gels are available, based on the same type gel from highly concentrated (20mg/ml)stabilized HA, which varies in particle size and subsequent indication. Restylane has a particulate size of 100,000 gel particles/ml, flows through a 27 gauge needle, and is indicated for mid-dermal applications such as deeper wrinkle reduction, as well as lip augmentation, nasolabial folds, and glabellar creases. Restylane Fine Lines has the highest concentration at 200,000 gel particles/ml. It can be injected through a 30 gauge needle, and is indicated for thin superficial wrinkles. The lowest concentration gel is Perlane at 8,000 gel particles/ml which is injected through a 27 gauge needle and is intended for shaping facial contours, correcting deep folds, and for lip augmentation. Restylane was FDA-approved in December 2003, Perlane received its approval in 2007. There are numerous manufacturers of HA injectable fillers which, in addition to Restylane, includes Captique and Juvaderm.
The universal HA composition makes the need for pre-injection skin testing unnecessary as the risk for hypersensitivity reactions is minimal. It is easily injected and flows nicely through small-gauge needles. While not permanent, its persistence is reported to exceed bovine collagen with estimates of between 4 and 6 months post-injection.Rare side effects, that I have not yet seen, include injection site inflammation at an incidence of 0.02% and local hypersensitivity reactions (swelling, erythema, and induration) at an incidence of 0.02% lasting a mean of 15 days.
As of today in 2008, HA injectable soft tissue fillers are the gold standard by which all future injectable filler materials will be compared.
The Future of Injectable Fillers and the Use of Fat
The landscape of cosmetic enhancements is evolving, with a significant shift towards using biologically-derived materials like autologous fat, enriched with stem cells, for more natural and potentially longer-lasting results. This approach not only promises a reduction in allergic reactions and side effects but also a more sustainable aesthetic improvement.
Understanding The Advertising Hype in Plastic Surgery
Summary: In the realm of elective cosmetic plastic surgery, advertising often promises minimal downtime and impressive results, but how much of this is reality versus marketing? This article delves into the truth behind the claims, exploring various procedures from injectables to laser therapies and invasive surgeries, providing a clearer picture of what patients can realistically expect.
Beard Skin, Ears, and the Male Facelift: Navigating Unique Challenges
Facelifts for men involve unique challenges, particularly concerning beard skin and scarring. Men considering this procedure should be aware of potential issues like beard skin displacement and the visibility of scars. These factors can affect the post-surgical care routine, including the possible need for laser hair removal.
