For a seven-year-old child with crooked teeth needs to be corrected in stages according to the type of malocclusion, which is divided into early correction and conventional orthodontic treatment. 1. Early orthodontic treatment: seven-year-old children with crooked teeth may be caused by early loss of milk teeth, the neighboring teeth have been reduced or have a tendency to reduce the size of the teeth, according to the situation of the need to make a gap retainer. 2. Conventional orthodontic treatment: for seven-year-old children if the front teeth of the anti-mandibular, need to use orthodontic appliances in the eight to nine years old period of orthodontic treatment, if after the early orthodontic treatment of malocclusion correction effect is not big, need to be in the period of 12 years old or so after the permanent teeth eruption of the whole mouth orthodontics. Seven-year-old children with crooked teeth can generally be corrected, but according to their own oral conditions, the corrective period and program may be different, specific recommendations to the hospital for examination after targeted treatment.