To place an implant after mastectomy, the surgeon will use the same incision that was used to remove the breast tissue. The implant may be placed directly under the skin, but it is usually put under the chest muscle.

Often, before an implant is placed, a doctor will first place a balloon (or tissue expander) beneath the chest muscle. Saline is added to the expander every 1 to 2 weeks to help stretch the skin and muscle. This may take several months. When the muscle and skin are stretched enough, the expander is taken out and an implant is put in.