The use of injectable fillers has become a mainstay of non-surgical facial rejuvenation. From lips to larger facial zones, a wide variety of differing injectable fillers exist. These injectable fillers may be different in chemical composition but most patients are only primarily concerned about how long they last and how much they cost.
Measuring effectiveness of injectable fillers is simply about how long they last. Since no injectable fillers are permanent, they are measured and compared by months of volume retention. It is somewhat difficult for patients to interpret length of effectiveness as one can only go by what the manufacturer claims as the number of months of ‘average’ persistence.
Comparing the effectiveness amongst the differing injectable fillers products is difficult if not impossible. This is because there are few, if any, clinical studies that have compared head-to-head any of the most commonly used filler products. I suspect there is a good reason for that…there is no incentive for any of the manufacturers to participate in such research.
Manufacturers do comparative injectable filler evaluations because they are required to do so by the FDA. They must compare themselves to what is known as the predicate device. In order for their product to eventually be FDA-approved for commercial sale, they must have human studies that compare their material to the predicate or known device. For fillers, this happens to be collagen.
The use of collagen as the predicate device is historic. The first injectable filler material was collagen and existed as the only approved filler from 1981 to 2002. While collagen is truly the predicate device, few use it today. Thus, it is so regulated by a Federal agency that newer fillers must be compared to a material that is largely no longer used.
While bovine and human-derived collagen injectable fillers still exist, their use is largely of historic interest only. This is because collagen only last a few months if that. No patient today wants an injectable filler that last less than three months. Every other different filler composition available lasts longer than just a few months.
What I find ironic, and the impetus of this writing, is that companies today tout their fillers as better than collagen. I just read in the Journal of the American Academy of Dermatology a study that demonstrated that treatment with injectable poly-L-lactic acid (Sculptra)was significantly more effective than human collagen (CosmoPlast) treatments. Such a finding is hardly unexpected or revolutionary, anything is going to last longer than collagen. But these type of studies are part of their FDA filing for widespread facial cosmetic uses.
In my Indianapolis plastic surgery practice I get asked everyday as to which injectable filler is best. Best, from a patient’s perspective, means how long do they last. Because of the lack of any comparative studies, all that one can say is that it is somewhere between 3 months and 9 months, which is where most of the fillers state that they last.
Dr. Barry Eppley
Indianapolis, Indiana