Hi there-
The only safe way to increase buttock volume and projection without and implant is to perform a Brazilian Butt Lift, in which fat is liposuctioned from areas where it is not wanted, and injected into the buttocks. The volume necessary is large, and so trying to substitute a filler material, including collagen, would be very, very expensive (restylane costs about $475 per 1 cc syringe, and we usually inject at least 500-600 cc per buttock cheek... you'd be looking at about $50,000, and this would only last 6-8 months!).
Find a surgeon certified by The American Board of Plastic Surgery who has a lot of experience in these procedures, and discuss your goals. The Brazilian Butt Lift is an excellent operation not only because of what is placed into the buttock, but also because of what is removed from the other areas.
