The pain is worse when you lie down, which is a typical clinical manifestation of pulpitis, and the pain is significantly worse at night. There is no 100% clinical explanation for this situation, but it is thought that there is a certain relationship with body position, when people are in an upright or sitting position during the day, the head is relatively in a high position, the blood supply to the head and face is relatively small, the swelling is not very obvious, and the pain is also mild. However, at night, when a person is in a lying position, the heart and head are on a horizontal line, and the head will receive more blood flow, the swelling will be more serious, and the pain will be more obvious.