Adult orthodontic treatment is generally not heavily adjusted because adults have adapted to the current occlusal relationship, but good results can be achieved with extractions in some patients with severe crowding and protrusion. This patient complained of anterior protrusion of the teeth, which affected the aesthetics. The patient’s face changed considerably after the surgery using tooth extraction orthodontic treatment. Risk of He Yuhong, Department of Stomatology, Jinan Military General Hospital: Adults generally have periodontal problems with gingival recession, and in this case, a black triangle in the lower jaw also appeared during treatment, which has some impact on the aesthetics. Patients who are particularly concerned about the black triangle should be cautious about orthodontics.