I am often asked by parents if the crowding in their child’s mouth can be treated with an expander in order to gain space and, hopefully, avoid the need for more complex treatment, including possible removal of teeth to gain sufficient space.
Expansion, as the term implies, is the expanding or widening of the palate and dental arches. The occurs predominantly in the upper jaw (maxilla). Whist we are able to achieve some mild expansion of the lower dental arch, it is limited in the amount and long term stability. Expansion is typically done in an arch that is too narrow, especially when compared to the teeth in the opposing arch.
Can expanders prevent the need to extraction of teeth in orthodontics?
The answer to this question is not straightforward. Whilst some space can be gained with expansion, the amount is often not significant in individuals with severe crowding of the teeth. In these individuals, even with expansion, extractions may still be indicated to achieve a stable and healthy outcome for the long term.
Can expanders be used at any age?
Expanders are best used at 8-9 years of age but can predictably be used up until 14-25 years of age when the bones of the upper jaw (maxilla) fuse. Expansion, therefore, cannot be carried out in adults and surgical intervention may required in order to achieve a successful outcome.
Are expanders removable appliances or are they fixed to the teeth?
Expansion appliances can be either fixed or removable. The fixed design is generally more efficient and results are better than with removable appliances. The fixed expander will remain in place for 3-4 months after expansion has taken place to allow the bone to readapt and stabilise. Braces can be utilised at the same time that the expander is in place.
In summary, expanders are useful appliances for treating malocclusions (bad bites). Whilst they are also used in order to gain additional space when mild crowding is present, in severe crowding, extraction of some teeth may be indicated. The broader smile that is achieved with expansion is also very attractive from an aesthetic perspective.