Tissue expansion is being used in reconstructive surgery for the treatment of a variety of problems in both children and adults. It is used in reconstruction in instances where there is not enough adjacent tissue to close a defect primarily or to repair with a local flap. Expansion is also indicated when repair of a defect by an alternative method such as a local, regional, or distant flap will result in an unacceptable donor or recipient site deformity.

The custom of soft-tissue expansion of the ears, nose, lips, and other body parts has been practiced by primitive cultures for aesthetic or religious purposes. African women of certain tribes place large plates in the lower lip to enlarge this structure. Women in Burma place rings around the neck to enhance linear growth.

Tissue expanders are Silastic balloons. The shape of the expander depends primarily on the site of expansion and the reconstruction needs. The standard shapes are round, rectangular, or crescent. Use of the rectangular expander provides the most effective surface area gained when compared to the round or crescent. Rectangular expanders gain 38% in tissue area of the calculated surface increase of the expander, where as round expanders gain 25% and crescent expanders gain 32% of calculated surface increase.

Two types of expansion are recognized and used clinically today: prolonged tissue expansion (PTE), in which expansion occurs over 1-6 weeks, and rapid intraoperative tissue expansion (RITE), in which the expansion is performed cyclically in the operating room. Prolonged tissue expansion allows resurfacing of even wider defects with neighboring skin similar in color, texture, sensation, and retained adnexal structures. 

The most serious complications are overlying skin necrosis, implant exposure, and extrusion. This may occur secondary to infection, trauma, erosion of flap due to folds in the expander, overly aggressive expansion, or placement of the valve over a bony prominence.