The use of devices to move teeth  or adjust underlying bone. The ideal age for starting orthodontic treatment is between ages 8 to 14 years while growth is still occurring. An evaluation for orthodontic treatment is recommended by the age of 7. Teeth can be moved by removable appliances or by fixed braces. Crowding of teeth can require extraction of teeth. Retainers may be necessary long after dental braces are placed, especially with orthodontic treatment of adults.