What am I talking about?
All results from any scar treatment are always temporary.
It's depressing but true. Doctors are in agreement that years down the road ALL scars will completely come back again.
Even treatments that stimulate native (our own) collagen --laser, dermabrasion, needling, etc-- and seem to smooth out scars are only temporary. All of these scars, even if they seemingly disappeared, will completely reappear.
Our scars will come back as we age. They are a lifelong battle that can never be won. I know! Sad but true!
I don't see how that can be true if say, your depressions were attached to the underlying tissue by scar tissue. Then you have subcision or a saline injection, which I have done on myself for my depressed scars, and that breaks the fibers, blood pulls under the scar and healing begins to fill the scar. In this case I don't think as you age the scars will reattach, it just won't happen.