Children’s large toothache may be due to caries, apical periodontitis, pulpitis and other diseases. 1. Caries: The causes of caries are bacterial infection, eating foods containing more sugar, etc. The child will have caries cavities and feel soreness when irritated. Caries cavities will appear in the affected children, and they will feel soreness when they are stimulated, which will be manifested as pain in children’s big teeth. 2. Periodontitis: Periodontitis can be caused by bacterial infection, physical irritation and other factors. The child will experience spontaneous pain, biting pain, swollen gums and other symptoms. 3. Pulpitis: Children with large toothache are also considered to be due to pulpitis. The cause of pulpitis is related to bacterial infection, chemical irritation, low immunity and other factors. Patients will experience localized pain, spontaneous pain, radiating pain and other symptoms. There are many causes of toothache in children, and parents are advised to bring their children to regular hospitals in time for relevant examinations to find out the cause of the disease.