I'm always fascinated by how asymmetric we all are.  It sounds like the line is just on the one side.  Usually the side of the face with more lines is the "sleep side" where we spend more time at night.

In your situation I would suggest a hyaluronic filler like Restylane or Juvederm layered over the Sculptra.  Sculptra is injected very deep in the dermis almost down to where the fat is.  It will provide good long term support there and help to keep it from getting worse.  But the line itself is probably in the mid to high dermis so layering something like Restylane right under it should help to bring it up more to level.  Please ask your dermatologist for advice.  Dr. I