This 9 year old boy has a crossbite of the upper right central incisor tooth (tooth number 11). Crossbites of adult teeth don’t self correct. There are a number of ways to treat these situations. You can use an upper removable appliance of some sort or braces to some of the teeth. There are advantages and disadvantages to either a removable or fixed approach. The major benefit of the fixed approach is you remove a lot of the compliance issues and therefore the fixed method is more predictable and often more comfortable for the patient.
In this circumstance we used braces to the upper front 6 teeth and some tooth filling material on the biting surface of the upper baby first molar teeth to open the bite to enable the movement of the 11 across the bite.
Treatment took 4 months.
Note that the crossbite of the upper left central incisor tooth (tooth number 21) self corrected when the lower left baby central incisor tooth fell out.
These are the photos at the completion of treatment after 4 months (4 appointments). Note that no retainers have been placed as there is still significant dental development to occur. Also note that the lower front teeth have straightened a bit without any treatment of them at all. This often happens once you straighten the upper teeth and remove any crossbites.
Further orthodontic treatment may be needed when all the remaining baby teeth have fallen out.
The major reasons for doing this treatment is to prevent unsightly wear to the edges and front surfaces of the upper and lower anterior teeth and to reduce the risk of gum recession. There is also an improvement to the cosmetic appearance of the teeth at an age where some kids are concerned with the way their teeth look.