In most cases, tooth decay in children must be treated, and only a very small number of milk teeth that will be lost and replaced within six months may be considered for observation or extraction. Children before the age of 6 are in the milk tooth row, and around the age of 6, they start to undergo the mixed tooth row period, where there are permanent teeth and milk teeth in the mouth. For cavities in permanent teeth, it is recommended to treat them as early as possible to prevent aggravation of the condition, which may cause pulpitis or periapical inflammation and delay the condition. For cavities in the milk teeth, for those who are about to fall out within six months, direct extraction can be considered or asymptomatic people will not be treated; for those who cannot be replaced in a short period of time, it is recommended that they be filled as soon as possible to prevent the disease from progressing and affecting the development and eruption of the permanent teeth. In addition, it should be noted that children’s milk teeth have a low degree of calcification and a large pulpal cavity, which can progress very quickly, so it is recommended to go to the stomatology department of regular hospitals for regular oral examination, timely detection of problems and early treatment.