Toothache and inability to eat normally caused by deep caries or periapical periodontitis, drinking white porridge every day should be the existence of chewing disorders. At this time, the dental disease should be treated, and the treatment methods are filling treatment and root canal treatment, as follows. 1. Filling treatment: Deep caries can cause toothache due to food embedded in the cavity, which affects normal eating. The treatment involves removing the decayed material, preparing a cavity and filling it with composite resin to repair the shape of the tooth. 2. Root canal treatment: Inflammation of periapical periodontitis is confined to the periapical tissues, causing occlusal pain and affecting the patient’s ability to chew food. Treatment requires root canal therapy, which removes the inflammatory material from the root canal and periapical area and then seals the root canal to eliminate the inflammation and complete the root canal filling. There may be other reasons for toothache, so it is recommended to visit the hospital promptly.