Sparse teeth can be corrected. Sparse dentition during the milking period does not require treatment because it is a physiological gap that facilitates the replacement of permanent teeth. During the replacement period, as the teeth are still in the replacement period, only observation is needed, and interventions can be made to address the etiology, such as trimming of the upper labial tether, extraction of multiple teeth in patients with multiple teeth, and change of bad habits in patients with bad habits, and orthodontic treatment in permanent teeth. For patients with sparse teeth, the orthodontic treatment of closing the gap is used. After removing the cause of the problem, such as the correction of the labial ties, the gap will be restored by itself if the permanent teeth erupt during the period of dentition, or treated with an orthodontic appliance if the permanent teeth are in the period of dentition, and the scattered gap will be closed with a fixed orthodontic appliance. For non-closable gaps, if the gap between the teeth is caused by congenital missing teeth, tooth volume and other factors, and cannot be closed by orthodontic treatment alone, the gap can be closed by concentrating the gap and then restoring it. Some patients with orthodontic treatment to close the gap need to be maintained, the retention method is the same as the normal retention, if the orthodontic treatment is followed by restoration then no retention is required.