Orthodontic treatment for children who have both deciduous (baby) teeth and permanent teeth developing is known as Early Treatment.
Most children don't have treatment until all their deciduous teeth have been lost, but in some cases early treatment is necessary for an immediate problem or to prevent or reduce a developing problem. Many children who have early treatment may still require orthodontic treatment at a later stage. As an example, an eight-year-old child may enough teeth and jaw development for an orthodontist to assess whether or not orthodontic treatment may be required in the future.
The upper front teeth are positioned “behind” the lower front teeth when biting together. An upper removable appliance may be recommended to gently move the upper front teeth forward, correcting the crossbite.
The width of the upper arch of teeth is slightly narrower in relation to the lower arch, and the lower jaw may compensate by moving to one side or the other for a comfortable bite. This sideways jaw movement is called a mandibular deviation. If it persists without treatment there is the possibility that it may cause a permanent asymmetry of the lower jaw. An upper removable appliance or a fixed 'Quad Helix' can be used to expand the upper arch to match the lower and thereby reduce or eliminate the sideways movement of the lower jaw when biting.
When a patient would like assistance to stop his or her thumb-sucking habit, a very simple upper removable appliance can be worn or, in more persistent cases, a fixed appliance like a 'Quad Helix' can be placed with loops behind the upper front teeth to prevent the thumb from entering.
The most common functional appliance is a 'Twin Block' which is an upper and lower removable appliance. The upper appliance has a built up wedge towards the back while the lower has a built up wedge towards the front – the wedges are designed and positioned so that every time the patient closes their mouth, the lower jaw is pushed forward. This persistently pushes the lower jaw forward, creating a potential space at the jaw joint.
If the patient has the inherent and natural growth potential, the jaw may grow towards this potential space and therefore improve the forward positioning of the lower jaw. Success of the appliance depends upon:
The patient must be at the appropriate growth stage of development to have the potential for success. The appliance is primarily recommended for patients who have a relatively small lower jaw.
A high degree of patient compliance for this appliance to be effective. the appliance must be worn at times apart from any additional advice given by the orthodontist such as during teeth cleaning or a sports activity. Almost all patients may still require fixed braces after the use of twin blocks.
For more complex cases, removable appliances may not be able to provide the same outcomes and fixed braces are required. As an example, severe crowding, large crossbites, and perhaps large spacing.