Brushing teeth with hot water does not cause bad breath, but brushing teeth with hot water and brushing teeth with cool water can cause the same irritation to the teeth, and even brushing teeth with hot water can cause necrosis and loss of normal mucous membrane cells in the mouth. It is recommended that patients should preferably brush their teeth with warm water, a temperature that is best contained in the mouth without any sensation in the teeth. The biggest advantage of using such water for brushing is that it protects the dental nerve from being stimulated and provoking it to inflammation or sensitivity symptoms. The temperature of brushing should be limited, but more importantly, the method of brushing should be the horizontal vibrating BASS brushing method, and the time of brushing should be better than 3 minutes to completely clean out the plaque.