Tooth pain is a very common symptom that not only affects normal life and study, but also has an impact on the appearance and health of the body in severe cases. In some patients, toothache can cause swelling of the face and even fever. Toothache is often caused by deep decay that affects the nerve and root tip of the tooth. However, the swelling of the face caused by toothache indicates that the inflammation in the tooth is very serious and has spread, and the swelling of the face indicates that the inflammation has involved the blood vessels and soft tissues of the face, which may be accompanied by systemic symptoms such as fever, headache, and weakness in severe cases. Swelling is usually a sign of an acute attack, and prompt treatment is recommended. If the toothache is caused by severe pulpitis, it is due to the spread of inflammation from the pulpitis to the root tissue, which then gradually spreads to the face through the bone plate. This causes a local tissue stress reaction, resulting in swelling of the face. If facial swelling occurs as a result of tooth pain, it is caused by pulp inflammation and apical inflammation, and it is recommended to take the appropriate treatment plan, such as root canal treatment and incision and drainage of pus, depending on the specific situation.