Kenalog for Dissolving ArteFill?

This is PMMA which is a PERMANENT filler. There is some degree of collagen formation surrounding each particle of PMMA. This component may be partially diminished by the use of Kenalog. However the PMMA will be unaffected by the Kenalog

No, Kenalog won't have an effect on the Artefill beads.
The carrier gel is bovine collagen and this component of the injection will dissipate, so you may see some lessening of the original fill effect over several months. However, once the bovine collagen is gone, the beads that remain are not going to "go away".
As noted in Dr. Placik's response, the Kenalog may have some minimal effect on your own collagen response to the PMMA beads, but that is all. Kenalog is a steroid and is used to reduce inflammation and in some instances is helpful in reducing thick scars. But for affecting the PMMA beads in skin, it won't lessen the number or the size of the spheres themselves.
Any patient considering permanent products should be well educated in how that product works. Patients who tend to scar easily or have problems with thick scars or keloids should be particularly cautious when using long term or permanent fillers which cannot be dissolved or easily removed.