Dental caries may cause tooth splitting, dentin hypersensitivity, pulpitis and other harmful effects. 1. Tooth splitting: If the cavity keeps expanding and weakens some parts of the crown, it may cause the crown to split, causing bleeding or pain when chewing. 2. Dentin sensitization: If the caries reaches to the depths, it causes sensitivity of the tooth nerve, which can cause soreness and discomfort when eating hot or cold food. 3. Pulpitis: If it continues to expand into the pulp cavity, it will cause inflammation of the pulp and spontaneous paroxysmal severe pain. It can also cause periapical inflammation and severe bite pain. Dental caries can also affect aesthetics and cause bad breath. When dental caries occurs, it is recommended to seek medical attention in a timely manner, follow the doctor’s instructions for relevant examinations, and carry out targeted treatment or therapy with the help of the doctor.