Dear Dee, There are many reasons not to use PMMA for buttocks augmentation the most important of which is that it is not approved for this use. There are many reports of complications with PMMA many resulting in very bad and permanent deformities and constant ongoing pain.To date, only two forms of treatment are approved for buttock augmentation, implants and fat transfers. The implants available use in the USA are very limited when compared to other parts of the world. For some patients though, implants are the best option. An increasingly popular option is the Brazilian Butt Lift(BBL) which uses your own fat to augment the buttocks. It is a technique that does require the patient to have enough fat for use so a consultation with a plastic surgeon is needed.Please stay away from PMMA injections. The risks outweigh the benefits.