When a filling is made of a metal material with good conductivity, or when the filling is adjacent to the pulp chamber due to a deep break in the tooth, hot and cold changes can be transmitted to the pulp nerve through the filling material or filling, causing tooth soreness. At the same time, some patients still do not pay attention to oral hygiene after filling, which leads to secondary caries, so that the cavity continues to expand and develop deeper, resulting in tooth soreness.