SENSITIVITY OF PIGMENTED MUCOSA AND SKIN TO FREEZING-INJURY

Pigmented areas of canine skin and oral mucosa were subjected to freezing in situ at various temperatures for the purpose of investigating possible differences in the sensitivity of epidermal cells to cold injury. Destruction of melanocytes occurred in the range of -4 to -7 °C, while squamous cells resisted injury even at -20 °C. Replacement of the lost pigmented cells occurred from the normal tissue at the periphery of the injured area. The experiments suggest that selective destruction of pigmented lesions in clinical conditions may be achieved by freezing tissue to -4 to -7 °C or colder, but not to exceed -20 °C in order to avoid destruction of squamous cells. The experiments also support wider use of cryosurgery for pigmented lesions of the skin and oral cavity. © 1979.