The common cause of big tooth pain is caused by tooth decay, which is also known as cariogenic, or it may be caused by dentin sensitivity or other factors. Large teeth are also molar teeth, which are easy to be decayed because the sulcus point gap is not easy to clean. It is difficult to reach the bottom of the sulcus by brushing or professional tools, and bacteria are easy to breed to cause tooth demineralization and cavity. If the tooth decay is not treated in time, the bacteria will further infect the nerve of the tooth and cause the symptoms of pulpitis, painful eating, or hot and cold water pain and night pain. Root canal treatment of the tooth is needed to relieve. Dentin sensitivity can also cause tooth pain. The outermost layer of the tooth is the enamel. If eating hard foods causes the enamel to be worn away, the dentin tubules are exposed and hot and cold stimuli pass through the dentin tubules and reach the nerve, and the pain is more intense. Large tooth pain may also be caused by trigeminal neuralgia, a branch of the trigeminal nerve that innervates the molar area and causes tooth pain, which needs to be identified with tooth decay. The pain can also be caused by gingival papillitis, where the gingival papillae are red, swollen and bleeding, which can also lead to tooth pain. Gingival papillitis requires local anti-inflammatory treatment of the gums. Large tooth pain needs to be identified as the cause, which may be a decayed tooth or an allergic reaction, and needs to be clearly diagnosed and treated as early as possible.