If a small child has a toothache, an oral examination should be performed and apical radiographs or surface tomograms should be taken. If there is a large gap between the milk teeth during the rapid development of the jawbone, resulting in food impaction, causing swollen and painful gums, you can use dental floss or dental flosser to clean up the food debris, spraying rehabilitation of new liquid, gold throat health, etc., to promote healing. If the permanent teeth in the process of eruption caused by the loosening of the milk teeth, gums appear swollen and painful, need to strengthen oral hygiene and clean, eat more chewy food, to speed up the absorption of the roots of the milk teeth, if necessary, extraction of milk teeth. If the cavity is large and sensitive to hot and cold stimuli, it is necessary to remove the decayed tooth tissue and use glass ionomer cementum to fill the cavity. In case of inflammation due to pulp infection in the cavity, the pulp can be removed under local anesthesia, and the root canal can be disinfected and filled with calcium hydroxide paste.