When the pain of tooth decay occurs during pregnancy, it is considered that the tooth decay has been deeper and may have affected the nerve of the tooth. At this time, if it is in the middle of pregnancy, or if the pregnant woman is in a better physical condition, root canal treatment can be done to treat the tooth pain by opening the pulp and drainage, root canal disinfection and root canal filling. If the pregnant woman’s physiological condition is unstable, conservative treatment can be done if necessary, which is to apply clove oil cotton balls for soothing treatment in the cavity of the decayed tooth. Clove oil can play a certain soothing and pain-relieving purpose to the tooth pulp. If it is a cavity, which is already very bad and cannot be preserved, and the local inflammation is heavy, the pain caused by this kind of cavity, sometimes in order to prevent the inflammation of this kind of cavity, which may spread and cause the infection in the facial space, can be extracted if necessary, and the operation of tooth extraction can be considered in the middle of pregnancy. Therefore, if tooth decay pain occurs during pregnancy, you should go to the hospital for a formal examination and treat it symptomatically through clinical diagnosis.