The best thing about using fillers is that you see the result IMMEDIATELY. Patients can ask for more product at that point if they desire it. See how the right side was smaller in the photo on the right?
Doctors have a variety of products to use to fill the midface volume that is lost as we "climb the ladder of life". When our table (midface volume) gets smaller but the tablecloth (the skin) stays the same size then sagging or wrinkling appears. The youthful face is round. Light reflects better and patients tell me they feel as if they are "glowing" after the filler procedure is done. It is also relatively painless because the product is mixed with local anesthesia. I think this photo shows clearly how you can improve the appearance of the facial skin when you "pump up the volume".