If you are not wanting to undergo a surgical procedure you can consider Sculptra. This is not an HA filler and works differently to give longer lasting results. Multiple treatment sessions may be needed to build the result you are wanting. I've included a video on how Sculptra works that I...
From the photos and description of your concerns Sculptra or HA fillers would not be an economical choice to restore your volume. Too much product would be needed and the results would not be permanent.
Thank you for the question and pictures. You may be unhappy with the look of your derriere and want more volume and firmness. A Sculptra BBL can help you have a firmer, more lifted butt by stimulating the natural production of collagen, causing the skin to become thicker and adding subtle volume...
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Everything you need to know about Nonsurgical Butt Lift