2 years old baby tooth bad pain can be based on the degree of caries dental filling treatment or root canal treatment. 1. If the baby caries does not affect the pulp tissue (i.e. dental nerve), only caries inlay pain or hot and cold stimulation pain when eating; at this time, we must seek medical treatment for dental caries filling treatment, that is, the use of dental filling materials on the caries of the defective part of the restoration. 2. If the baby caries caused by pulp tissue infection, that is, spontaneous pain, biting pain or hot and cold stimulation pain and other symptoms of pulpitis or periapical periodontitis; must seek medical treatment for dental root canal treatment, that is, to clean up the inflammation and necrosis of the pulp tissue in the root canal in order to effectively stop the pain. It is recommended that 2 year old babies with bad teeth should seek medical attention for symptomatic treatment in order to avoid delaying the condition.