Is There a Cumulative Effect with Juvederm?
It should be generally assumed that all of the Juvederm you receive will be absorbed by the body. In other words, the effect is not permanent and will not last. There is some speculation that repeated injections may stimulate collagen growh in the field injected. This collagen may or may not be cosmetically significant.
Hyaluronic acid fillers like Juvederm cause a gradual stimulation of collagen over time. This is best accomplished if you start with a full correction and touch up as needed, regularly. The same is true of Restylane.