Gangrene is the decay or death of a body tissue due to restricted blood flow. Infection, disease, injury, post surgery, and inflammation of blood vessels (as in buerger's disease) can cause gangrene. Gangrene is divided into three types: dry, moist and gas. Dry gangrene develops when blood flow in the tissues is restricted as a result of blocked arteries. In order for the tissues to work properly they need oxygen and energy that is supplied by the blood. If the arteries are blocked tissues lack these essentials and they therefore decay and eventually die. Lack of blood also makes the affected tissue cold and black, it then dries and after a period of time drops. Moist or acute gangrene is a condition that occurs when an anaerobic bacteria infects the dead tissues. Moist gangrene mostly affects the toes, feet or legs. The bacteria in the tissue grow producing gasses and poisonous toxins giving rise to a condition known as gas gangrene. Gas gangrene is a type of moist gangrene and may develop due to Diabetes mellitus, cancer , and frostbite. There are so many other causes that could lead to gas gangrene. The symptoms of moist gangrene include a rise in temperature, pain in the affected areas and acute anemia. Gangrene can be treated by debridement , intravenous , intramuscular and antibiotics therapy. Other treatments include medication (to control discomfort) and hyperbaric. Amputation may be necessary in other cases.