The possible reasons for eating sweet tooth pain are as follows: Firstly, tooth decay, tooth decay is a dental hard tissue infection, which will cause tooth defect and make dentin tubules exposed, after dentin tubules are exposed, it will produce pain and sensitivity when encountering cold, hot, sour and sweet, such as cavity is very big, the infection has spread to the pulp, and sweet and sour food will cause severe pain. Second, suffering from periodontitis, chronic periodontitis will cause the alveolar bone resorption, gum atrophy, making the root of the tooth exposed, which will lead to the pain and sensitivity of the whole mouth teeth to sweet food. Third, there are cracks on the surface of the teeth, and it is difficult to observe the hidden cracks through the naked eye. The main symptoms of hidden cracks in teeth are painful eating sweets, sensitivity to hot and cold, and even painful biting. Fourth, wedge-shaped defect of the neck of the tooth, which is mostly caused by lateral brushing or brushing too hard to cause the defect of the neck of the tooth, thus causing tooth sensitivity and pain.