Prefabrication of bilaminar-epithelialized composite flap with tissue expander and cultured keratinocytes

This study investigated the feasibility of prefabrication of a bilaminar-epithelialized flap by using a tissue expander and cultured keratinocytes, for reconstruction of perforate defects in the oral cavity and upper aerodigestive tract. In each of six rats, a 10-ml volume expander was implanted under the inferior epigastric flap and a thin silicon catheter was introduced into periexpander space. Seven days after implantation, 10 x 10(6) cultured keratinocytes, isolated from inbred donor rats, were suspended in fibrin glue and injected into the periexpander space through the catheter (n = 4 of 6). The expansion was started immediately after cell inoculation and lasted at least 3 weeks at the speed of 2 to 3 ml every 5 to 7 days. At the end of expansion, the periexpander space was opened and the capsule around the tissue expander was found to be covered completely with a neoepithelium. Thus, a bilaminar-epithelialized flap based on femoral vessels was elevated and successfully transferred to cover the excisional perforate defect in the oral cavity with the neoepithelial side as inner lining. All flaps treated with 10 x 10(6) cultured keratinocytes survived with complete wound healing during a 1-week follow-up (n = 4 of 6). Both macroscopic and histologic findings demonstrated that a bilaminar-epithelialized composite flap can be fabricated by using a tissue expander and keratinocyte-fibrin glue suspension.