Which Filler to Labiomental Groove and Bottom on Chin?

A repeat fat injection may be the best, but I have added fillers like Perlane or Juvederm into the area to improve the contour appearance.

I think that with proper placement and with just the right amount of filler, you could get an excellent result with almost any of the fillers currently available.  My preferred filler for that area of the chin however would be Radiesse.  It is firm enough to give a lot of lifting for the amount of material it injected and long-lasting enough to give you a great result for an extended period of time.  I hope you find this helpful.