Whether or not to extract the lower row of upper teeth with one missing lateral incisor needs to be judged based on the oral condition, such as reference to the Bolton Index, aesthetic needs, etc. It is not necessary to extract a lower tooth to correct the problem.
The Bolton Index is the ratio of the sum of the widths of the 6 teeth of the lower front teeth to the sum of the widths of the 6 teeth of the upper front teeth, which needs to be examined by a physician to make a judgment. If a patient’s Bolton Index is within the normal range due to malocclusion, orthodontic treatment can be considered without extracting the lower teeth. Loss of lateral incisors on the upper front teeth, left-right asymmetry, will affect aesthetics, you can consider moving the cusp, grinding and changing instead of the lateral incisors, or leave the lateral incisors of the gap, later implant treatment, do not necessarily have to extract the lower row of teeth.
For orthodontic treatment whether to extract teeth, different doctors treatment program will be abnormal, it is recommended to fully communicate with the doctor, especially when it comes to aesthetic problems, it is recommended to go to the regular hospital stomatology consultation.