Comparison of Dermal Substitutes in Wound Healing Utilizing a Nude Mouse Model

BACKGROUND Dermal skin substitutes have become a standard of care in burn treatment. OBJECTIVE To compare and assess wound contracture reduction and histologic incorporation into the wound, dermal substitutes were implanted into full-thickness skin wounds in nude mice. MATERIALS AND METHODS Thirty-seven mice received a full-thickness 2 x 2 cm dorsal skin wound, and were either implanted with an acellular dermal matrix, Alloderm, Dermagraft-TC, Dermalogen, or Integra or assigned to the control group (with no dermal substitute). At 28 days postsurgery, the wounds were assessed for contraction, epithelialization, and other histological characteristics. RESULTS Each dermal substitute decreased wound contracture, but Alloderm and the acellular dermal matrix did so significantly compared to the control (P < .01 and P < .03, respectively). Within-group and control comparisons showed no significant differences with respect to the presence of dystrophic calcification, squamous hyperplasia, infiltration of neutrophils, fibroblasts, and macrophages, epidermal keratinocyte stratification, or collagen fiber configuration. CONCLUSIONS Integra elicited the greatest foreign body response. Although the Dermalogen group had the thickest elastin fiber fragments, Dermagraft may have initiated the earliest elastin fiber formation in the wounds. While all dermal substitutes were incorporated into the wound bed and wound contracture was decreased, acellular dermal matrix and Alloderm, both human skin-derived products, produced less contraction and the thickest new "dermis" in the healed wounds compared to the control or synthetic dermal substitutes.