There is a LOT of information on the internet which is simply not true and misleading about buttock augmentation. If you look you can find glowing reviews of almost every technique as well as people cursing the day they had the procedure done. When it comes to PMMA injections you will see a trend in the information. The people who are claiming how good PMMA injections are and how safe it is to do are not actually medically trained let alone doctors. Whereas the negative information is generally from two sources, doctors and people who have had the treatments and have problems. There are some posts from patients that have had the injections and are happy though frequently these posts are found to be actually advertising for centers or doctors performing these procedures. In the USA PMMA is not FDA approved for injection into the buttocks. In fact, I am not aware of liquid PMMA being FDA approved for ANY purpose. If treatments were so safe and results were so good, don't you think a company would have submitted their product to the FDA for approval by now. The technique has been around for many years. The plain truth is that the treatment has a very high rate of complications. These complications can be quite deforming of the body and, in some cases, life threatening. You mention "medical grade" PMMA. While this may be some comment on the purity or the cleanliness of the product, without FDA supervision you cannot be sure that the material is sterile and suitable for injection. A large portion of the complications seen are related to infections. No matter how "trustworthy" you might feel a doctor is, the material he/she is using is most certainly NOT. In Miami I see a lot of patients interested in buttock augmentation. I perform a good amount of butt augmentation as well. The technique that I use is fat transfer. It is safe, reliable, and provides a natural result using your own tissue. In cases where there is not enough fat for transfer (rare, though it does occur) implants can be used. Fat transfer is, in my opinion, far superior for natural look and feel. I hope this info helps!