This may have arisen as a result of extra proliferations of the dental lamina or one of the normal tooth germs, at an early stage, actually splitting to form two tooth germs. These extra teeth are also called supernumerary teeth.
- They can occur in any part of the mouth and may be related to a particular tooth group. Hence they can be incisoform, caniniform and molariform.
- However, they tend to be rare in the primary dentition but common in the permanent dentition.
- They affect females more than males.
- They are ten times more frequent in the maxilla than in the mandible and tend to be in the anterior region.
- Their form can vary from a normal-looking tooth to conical or tuberculated shaped teeth. The former is often the result of a permanent tooth germ splitting at an early stage and causing two identical teeth to form. Where the extra tooth is identical to the tooth of the normal series, then it is termed a supplemental tooth.
Occasionally an extra tooth causes no problems and is accommodated into the dental arch without disruption to the occlusion. More often than not it leads to localized crowding and this is remedied by the extraction of the tooth that is in the least favorable position.
Syndromes associated with hyperdontia:
These syndromes are all rare but probably the best known is cleidocranial dysplasia where many additional teeth develop but fail to erupt.
Supernumerary teeth may cause no problems and may erupt in ectopic sites such as the palate and may be simply extracted.
At other times supernumerary teeth may impede the eruption of permanent teeth or cause them to be deflected from their normal path of eruption. If this occurs, then a surgical extraction of the supernumerary tooth is required. Once a clear path of eruption has been established, the unerupted permanent tooth is likely to erupt uneventfully.
Where it may be deemed that this tooth has impaired eruptive potential, then often the unerupted tooth is surgically uncovered and an orthodontic bracket and gold chain is attached. The tooth is recovered and the mucosa is sutured back in place. Subsequent gentle pressure via an orthodontic appliance will pull the errant tooth into a normal position.
Occasionally, supernumerary teeth which have not led to problems may be left in order to avoid a surgical extraction. Where this occurs, as with any unerupted tooth left in situ, it will need to be monitored by having a radiograph taken at least every 2 years to ensure no pathological changes have occurred, such as resorption of adjacent teeth or cyst formation of the dental follicle.