Tissue Expansion

Tissue expansion usually involves an implant which is gradually filled with saline to slowly stretch the skin and expand the dermis. Tissue expansion works by a principle called stress relaxation which means that, over time, the dermis expands in such a way as to reduce the tension on the skin. When the tissue expander is removed, the skin retains much of the excess that developed as a result of stretching over six or more weeks. Although the dermis thins during the stretching process, a vascularized capsule forms around the implant which helps support the overlying skin.

Tissue expansion is used as a way to create more skin and laxity to close large skin defects following surgery. In the case of breast reconstruction, tissue expansion is used to increase the skin laxity around the eventual permanent implant, to provide softness and a more natural shape (ptosis).