Sculptra is natural lactic acid polymerized into longer chains.
It has not been studied in the breast but it should help enlarge the tissues.
Sculptra is not used for creating breast fullness, but can safely and effectively treat wrinkles in cleavage area, tighten and improve the appearance of chest skin. If you are averse to breast implants, consider fat transfer. This is a new and exciting technique, with natural results achieved through your own body's fat. Few people are experts in this area, so be sure to research and find a good surgeon. Best of luck!