To heal a wound, the body starts to grow many different types of cells in the wound area such as blood vessels and builder cells (fibroblasts). Many of these cells only grow when there is water. When there is no water instead of building new tissue inside the wound, the existing tissue will start to die. So the wound bed should never be fully dry. Keep the wound bed moist by covering it with appropriate dressing material. Often, by just covering the wound with appropriate dressing, it will start to heal. If a wound is too dry, even with proper dressing, then it needs extra moisture, a wound gel or wound ointment.
The traditional wet-to-dry dressing – wet gauze then dry gauze — actually dries so fast it can create a dry wound bed. This is the reason we seldom use this method these days.
Only in very rare cases when wound healing cannot be achieved, leaving a wound bed dry might be an option. In these cases, dry dead tissue (eschar) is protective of the tissue underneath even though it hinders wound healing.