Possible clinical causes of toothache after waking up include bruxism, periodontitis, chronic pulpitis, etc. 1. Molar disorder: People with this condition will unconsciously chew and clench their upper and lower teeth during the night, which will result in soreness of the biting muscles and pain in the temporomandibular joints. 2. Periodontitis: People suffering from this disease will have different degrees of gum recession and root exposure, which is prone to dentin hypersensitivity phenomenon, clinical manifestations of waking up with tooth soreness, pain and other symptoms. 3. Chronic pulpitis: this disease will cause people suffering from the disease of the pulp is infected and necrosis, the pulp cavity will appear inflammatory secretion and make its internal pressure rise, thus causing pressure on the surrounding nerves, the clinical manifestation of dental pain discomfort. It is recommended that people with this condition should go to a dental hospital to get a clear diagnosis, so that targeted treatment can be carried out.