A quantitative method for the evaluation of ulcer healing has been developed. The method consists of calculating an ulcer healing efficiency ratio (zetaz) interpreted as the second derivative of the regenerated ulcer area over time. The zetaz value is in direct proportion to the acceleration of healing, and in inverse proportion to the initial ulcer area. In order to test this method, we measured the surface area that was delimited by the ulcer edge and the initial depth of the ulcer in three patient groups. The first and third groups were treated with a cellulose membrane and the second group-with Unna boot. The initial ulcer area was the same in groups 1 and 2, but in group 3, it was six times smaller. The greatest zetaz value was obtained in group 3, the smallest-in group two.