Sculptra butt injections, including for a hip dip, require an initial series of 2 to 3 treatments spaced one month apart. Thereafter, ‘top up’ sessions are needed every 18 months to 2 years, in order to maintain the buttocks enhancement. Results begin to show 4 to 6 months after the third initial treatment. A Sculptra butt lift is not permanent. Results need to be maintained. The effects will go away after about two years. The length of time it lasts depends on each person’s response to the substance. Some say it lasts less than two years, and some say it lasts up to three years.