There are certain times when ice is useful in relieving toothache, usually in septic inflammation, especially in septic apical inflammation, when the corresponding area appears to be septic and swollen, and when cold compresses or cool water is applied, the patient will feel a significant reduction in pain. Because the cool water constricts the local blood vessels, the corresponding swelling is also reduced, and there is a corresponding process of pain reduction. Although the pain is reduced but the pain still exists, many patients will come to the hospital with cool water and ask for treatment of toothache. Therefore, the treatment of toothache with cold water is not a cure, but it is necessary to go to a professional stomatologist and have the tooth pulp treatment.