The ongoing fight to delay, and in some cases reverse, the aging process could be on the verge of getting two important new allies. If approved by the U.S. Food and Drug Administration (FDA), dermatologists are confident that injectable silicone and hyaluronic acid gel will be the soft tissue fillers of choice among aging men and women looking for a natural-looking, long-lasting fix. Speaking today at the American Academy of Dermatology's 2003 Annual Meeting in San Francisco, dermatologist Rhoda S. Narins, MD, Clinical Professor, Department of Dermatology, New York University Medical Center, New York, NY, discussed these two new fillers and their advantages over the fillers currently available in this country.
Until it was banned by the FDA in 1992, silicone was used in the United States for many years with much success to treat wrinkles and acne scars as well as to enhance areas such as the lips, cheekbones and the chin. For these types of procedures, the safety and efficacy was compromised when silicone was diluted with foreign substances, such as mineral oil, or when it was injected in large volumes in an area during one treatment session.
It wasn't until the late 1990s that a form of silicone known as liquid injectable silicone was developed and approved by the FDA for use in the eye to treat chronic retinal detachment. This new, medical grade silicone is now being studied in the U.S. to determine its safety and efficacy as a permanent filler for aging skin.
"What makes silicone so unique from other fillers is that the results are permanent," explained Dr. Narins. "With other fillers, patients have to routinely come back to the office to maintain their results. But studies are showing that once the results are achieved with injectable silicone, there is no need for further treatments unless it becomes necessary as the patient ages.
Using the micro-droplet technique to ensure the best and safest results, tiny amounts of silicone are injected at four to eight week intervals until the desired result is achieved. Depending on the depth of the wrinkle or scar, no difference may be seen for one to three treatments.
"When the microdroplet technique is used with a purified silicone product by a dermatologic surgeon experienced in the technique, side effects are rare," explained Dr. Narins. "However, the decision to use silicone must be between the patient and the dermatologic surgeon after any potential complications have been weighed based on the patient's medical history."
"We're extremely hopeful that once the FDA-monitored studies are complete, liquid injectable silicone will be readily available for patients here in the U.S.," added Dr. Narins.
Another new soft tissue filler on the horizon that is not yet FDA approved but is being studied in the U.S. is a non-animal form of hyaluronic acid gel. Hyaluronic acid is a naturally occurring component of the skin that is the framework or medium that cells live in. In gel form, hyaluronic acid binds to water and provides volume to easily fill in vacant wrinkles left by tissue loss, making it suitable for larger folds of skin around the mouth and cheeks. This highly purified, non-animal form of hyaluronic acid has already been approved for use as a filling agent in Canada, Europe and Australia.
A new multi-center clinical trial has shown this non-animal form of hyaluronic acid gel to be a superior filler to bovine collagen for the persistent improvement of nasolabial folds - the deep lines visible from the nostrils to the corners of the mouth. Six months after treatment was completed, study findings indicated that less volume of hyaluronic acid was needed to achieve optimal cosmetic results, and patients overwhelmingly preferred the gel substance to collagen.
"In this comparative study, each investigator was given an envelope with instructions on which substance was to be injected in each side of the patient's face," explained Dr. Narins. "Patients were treated every two weeks until treatment was complete. Based on clinical data from 134 patients in six centers nationwide, our overall conclusion is that hyaluronic acid for the treatment of nasolabial folds works better, lasts longer and requires less volume compared to collagen. At the same time, this non-animal form of hyaluronic acid offers the added benefits of no allergic reactions and no potential transmission of disease."
Dr. Narins is confident that once FDA-approved, hyaluronic acid can be used effectively to augment and contour acne scars, enhance lips, fill in hollow areas such as the cheeks and under the eyes, and improve a receding chin.
"Based on the study results that we've seen, I expect that when silicone and hyaluronic acid are approved by the FDA that the demand for them will be overwhelming," said Dr. Narins. "Both fillers provide many unique benefits over other fillers currently being used to treat aging skin, but patients need to be sure that they select a qualified dermatologist or dermatologic surgeon experienced in these new fillers and that they weigh the pros and cons of each treatment carefully."
