There are many causes of toothache during breastfeeding, commonly pain of cariogenic origin, but also pain due to gingivitis. Toothache during breastfeeding is a common phenomenon, mainly due to changes in hormone levels during pregnancy and inflammation of the gums causing gingival papillitis, which sometimes leads to toothache. It may also be caused by the lack of calcium during breastfeeding. The lack of calcium in the body leads to the loss of calcium material in the teeth, which causes tooth demineralization and tooth decay. If the tooth decay is not treated in time, further infection by bacteria causes inflammation of the tooth nerve and symptoms of pulpitis, resulting in painful eating, or spontaneous pain, aggravated by temperature stimulation, and serious night pain. Early stage of tooth demineralization needs timely fluoride application to promote tooth remineralization. If the cavity has already appeared, the decayed part can be removed with a drill and the tooth can be filled. If the tooth nerve has been damaged, nerve killing treatment is needed. Toothache during breastfeeding may also be caused by trigeminal neuralgia, which is an inflammation of the branches innervated by the trigeminal nerve, resulting in tooth pain. It can also be caused by dentin hypersensitivity, which may be caused by wear and tear of the tooth enamel, exposing the dentin and causing pain through hot and cold stimulation of the dentin tubules stimulating the nerve. Therefore, the cause of toothache during breastfeeding needs to be identified, and if it is caused by tooth decay, it needs to be treated as soon as possible. If it is gingivitis, the infection needs to be controlled in time.