Allow me to "fill you in" (Part I of IV)

Injectible fillers: where we started, where we are, where we are going

In the next 3 blog entries I will discuss all of the fillers available on the market. To simplify this, I have categorized them by their longevity:
I. Temporary short duration fillers
II. Temporary long duration fillers
III. Permanent Fillers

This single entry is an introduction for the general characteristics and qualities that differentiate each filler.

As cosmetic surgery continues to become more mainstream, injectible fillers have become the appetizer which many more patients are willing try before sitting down for a full meal. Fillers are wonderful in that they are a quick fix, with minimal to no downtime, affordable, and work well in the right situations. As fillers continue to become more popular, more and more fillers are becoming available. This has become a point of confusion to many patients, and quite honestly many doctors have asked me for my opinion to what is the best filler for each area. This blog entry is written to give you the “what you need to know” for fillers.

What characteristics do we look for when evaluating a filler?
An ideal filler should be:
1. biocompatible
2. predictable
3. easy to inject, with little downtime
4. inexpensive
5. long lasting-or permanent
6. reversible
7. appears natural

What makes a filler different than another?
Fillers differ in
1. What they are derived from
Since Neuber’s use of fat in 1893, and the short-lived use of paraffin in the 1900’s the options for fillers now available to us are tremendous. In the 1940s silicone injectable fillers were being used for facial augmentation with success, but with the misuse of adulterated product a growing number of complications lead to its ban by the state of Nevada in 1964. In 1965 the FDA classified silicone as a class III medical device. Since 1997 is has been approved only in the treatment of a detached retina.
In the 1970’s xenografts (derived from a different species) were among the first fillers used, and FDA approved in 1981. These were Zyderm and Zyplast, which were bovine (cow) collagen, and Fibrel porcine (pig) collagen. These fillers required skin testing due to their high rate of allergies (3 in 100). This went against the grain of today’s cosmetic surgery patient and spawned the birth of human derived collagen, Cosmoderm and Cosmoplast, in 2003. These have replaced the use of Zyderm and Zyplast. Shortly thereafter, hyaluronic acid fillers (Restylane, Perlane, Juvederm) became popular and had a much lower rate of allergic response, not needing any pre-testing.

2. Size of the particles in the filler affects viscosity, and therefore duration
Fillers consist of small particles in a gel matrix carrier. Generally speaking, the larger the size of the particle, the longer duration the filler lasts and the greater its viscosity. Additionally, the larger the particle size the greater chance for lumpiness upon injection. Restylane Fine Lines contain 200,000 particles/ml, Restylane 100,000 particles/ml, and Perlane has 10,000 particles/ml. Perlane has the least amount of particles, but its’ particles are the largest and therefore has the longest duration of effect, but is more likely to be lumpy if injected too superficially.

3. Concentration of the filler affects viscosity and duration
The higher the concentration of filler, the longer it remains in its injected site. Juvederm (24 mg/ml) appears to be the highest concentrated FDA approved hyaluronic acid filler available (Restylane, Perlane 20 mg/ml). We will further discuss these specific and other fillers in the sections to follow.