Soft tissue fillers are helpful to a certain extent in the average case. For one, the absorbable ones (Restylane, Captique, Hylaform, Collagen, etc) really don’t last very long. This story says up to six months. It is probably 1/3 to 1/2 of that in the average patient.
The more permanent methods can be really scary as you age. Goretex, in my not-so-humble opinion, belongs in ski jackets and not your lips. I have seen a case or two in which it got infected and it put a serious mark on the patient’s appearance. This story is a bit too rosy for my tastes, but you can read it all the same.