There are several possibilities: 1. deep caries, when there is deep caries, food may be stuffed into the cavity, which will produce pressure on the pulp cavity, so there will be pain, then the caries can be removed and the shape of the tooth and the adjacent relationship can be restored, so the food cannot be embedded into the cavity, and the pain will be relieved. 2. inflammation of the periapical region of the tooth, there is biting pain, so when eating In this case, it is necessary to do a radiographic examination to confirm the diagnosis of apical inflammation, and root canal treatment can be done to remove the nerve of the tooth. 3, tooth decay eating and touching special pain, it may be due to the exposure of the pulp cavity, and the pulp is touched when chewing food, there will be a painful phenomenon, and it is especially painful, then it is also necessary to do nerve extraction treatment, and then do a thorough root canal treatment. 4, tooth decay eating and stuffing If it is particularly painful, it may be due to the tooth splitting, so the tooth will move when biting, so the phenomenon of pain will occur, usually the splitting part needs to be removed, if it is a crown root fracture, the whole tooth needs to be removed in this case.