Not everyone agrees that second-degree burns require grafts or other treatments to heal. "Most burns heal without a skin graft. They mostly heal with a Band-Aid," says Robert Sheridan, a surgeon at the Shriners Burn Institute at Massachusetts General Hospital in Boston. "There's a long history of autologous [derived from the patient] products for burn treatment, and they all suffer from high costs or neutral results." The upcoming U.S. study won't compare ReCell against no treatment, so this issue is unlikely to be resolved soon.

As a complete replacement for skin grafts, ReCell only works against severe second-degree burns--deeper, third-degree burns have destroyed the layer of skin that the ReCell solution would be able to repopulate. But the spray may be useful in treating more severe burns in conjunction with other approaches, as well as for treating existing scars. Wood, director of the burns unit at Royal Perth Hospital, uses ReCell in a process called scar remodeling, in which the cell spray helps repopulate scarred skin with melanocytes so that it more closely matches the patient's original skin tone. She also uses it in combination with other treatments, such as the skin-growing scaffold Integra, to reduce scarring and improve healing time.

"I use this technology in combination with all the other traditional technologies, and I can improve the outcome and the speed of healing," says Wood, who is also co-founder of the McCombs Foundation, a nonprofit dedicated to burn research and scarless healing. Royal Perth Hospital once had a long waiting list of patients for reconstruction surgery to fix the deep scars that accompanied third-degree burns. Now, she says, no waiting list exists. "Our reconstruction rates are going down because people don't need it. Because we're doing more at the beginning, they don't need the secondary scar work."