A tissue expander is a temporary implant that can usually be filled gradually. It is intended to stretch skin and soft tissue in a controlled way in preparation for later reconstruction. A common use is breast reconstruction after a mastectomy.
Depending on the system and treatment plan, filling takes place in several stages. The expander can later be replaced with an implant intended for long-term use, or another reconstructive method may be used. Timing and extent depend on the tissue and medical situation.
A wish to move from one bra size to another does not automatically justify using an expander. Risks include infection, pressure damage and problems with wound healing. Treatment requires regular checks and an individual plan.