Generally speaking, the normal orthodontic age is 10- 12 for girls and113 for boys, because it is easy to wear fixed appliances at this age. There is another stage, that is, in the deciduous period, which generally refers to 3-6 years old, that is, the correction of children's deciduous teeth, mainly aimed at the correction of bad habits. For example, if a child spits out his tongue easily, it will cause mouth opening deformity and his tongue will be pressed into an O-shape. At this time, they should make movable appliances that children can put on and take off, so that bad habits will not be seriously deformed in the future.

There is also a stage, the mixed teeth stage, and the replacement stage of deciduous teeth and permanent teeth. This stage is usually around 7- 1 1 year, which is a good time for correction. At this time, if the deciduous teeth have long since fallen out and the permanent teeth have not erupted, the teeth around this place will be pressed to a sparse place, and the permanent teeth will have no place in the future, which will also cause uneven dentition. Therefore, as long as it is found early, every age stage is the best age, and the dentition is uneven. The sooner you find it, the sooner you correct it, the sooner the better.