Department of Surgery, University of Michigan Medical School, Ann Arbor.
Histologic quantitation of the thickness of human tissues that were expanded using silicone expanders showed that the epidermis underwent significant thickening after 5 weeks to 5 months of expansion. The dermis and subcutaneous tissue, on the other hand, were significantly thinner after expansion. Capsules were formed in all 19 patients. The capsule was significantly thickest after 2 to 2.5 months of expansion. Expanded tissues 2 years after cessation of expansion had the same thickness as control tissues and had no remnant fibrous capsule.