I would recommend only FDA approved fillers!
having never heard of synthol, I did a quick internet search and frightened myself significantly. I would never recommend the injection of a non FDA approved filler. Many of us are still digging out silicone and other supposedly harmless fillers from people's body's. If you can't find a board certified plastic surgeon or a board certified dermatologist who uses a type of filler then you need to stop! We are as money hungry as the next guy, and if we thought it was safe we would inject it. However, it is not worth my medical license to inject something on the fringe when there are many great FDA approved fillers you can use that should last at least 18 months if not more. I am sorry to hear that fat has not worked, although it usually takes a minimum of two injections. Please see board certified dermatologists and or plastic surgeons and get another opinion. Best of luck.
Synthol as a filler for gynaecomastia surgery crater scar (divot under nipple)
As you have tried the fat injections to no avail I think the synthol is worth a go. If you do not like it, it can be removed
Indentation Concern Following Gynocomastia Surgery
Your incisions will go through a maturation #process after gynecomastia surgery. For the first few months they will be red and possibly raised and/or firm. As the scar matures, after 6-12 months, it becomes soft, pale, flat, and much less noticeable. You may experience numbness, tingling, burning, “crawling”, or other peculiar sensations around the surgical area. This is a result of the #healing of tiny fibers which are trapped in the incision site. These symptoms will disappear. Some people are prone to keloids, which is an abnormal scar that becomes prominent. If you or a blood relative has a tendency to keloid formation, please inform the doctor.
Also, as you heal, the area may feel “lumpy” and irregular. This, too, decreases with time, and massaging these areas will help soften the scar tissue. The #compression garment helps reduce the swelling, and the longer it is worn, the more quickly you will #heal. It can also assist in the retraction of the skin. If you have any concerns about #healing, its best to ask questions of your surgeon or their nursing staff. It's possible the indentations can be addressed with cosmetic filler(s) if eligible.