Tooth pain using cold water does not hurt may be the existence of acute pulpitis of the affected tooth, as follows. 1. When acute pulpitis occurs in the affected teeth, hot and cold stimuli can stimulate or aggravate the severe pain of the affected teeth. When pulpitis causes pus or partial necrosis of the pulp, there is gas in the lesion product, and the gas expands when it is heated, and the pressure in the pulp cavity increases, causing pain in the affected tooth. Cold water can make the gas contract, reduce the pressure in the pulp cavity, and the pain can be relieved. 2. The affected teeth may have deep cavities or non-carious diseases leading to dental defects, and may have spontaneous paroxysmal pain, night pain and other symptoms. There may be other reasons for tooth pain to stop when using cold water, so it is recommended to go to the hospital in time to clarify the cause of the disease and then carry out targeted treatment.