Medical science is not an exact science in the same way that chemistry and physics are. The reasons for this is because we are dealing with complex biological entities, and they are each and every one of them completely different; while the carbon atom reacts the same way under the same conditions, biological entities most certainly do not. One great example of this is the phenomenon of hyperdontia, or supernumerary teeth.
What are supernumerary teeth?
The human mouth has 32 teeth in it…most of the time. We have an idea that we are “meant” to have 32 teeth, and this is how our mouths are spaced, not counting the extra 4 wisdom teeth that many of us simply do not have the space for to begin with. On top of this, many people exhibit more than 32 teeth. Supernumerary teeth can appear anywhere in the mouth, and can overlap with existing teeth, or grow in seemingly random locations in the mouth. There are many ways in which these extra teeth can appear:
- Supplemental teeth are teeth that grow just like the other ones but are slightly different in their position. They can appear further up the gums, on the roof of the mouth, between the lip and the gums, but are fully functional teeth
- Extra molars are the fourth and fifth molars that tend to appear in a similar pattern; they grow behind the third molars, and almost always are impacted, and need to be removed. There is simply no room in the human mouth for more molars, and they grow to the detriment of other teeth in the mouth
- Tuberculate or barrel shaped teeth are ones that are not completely formed, and are rounded, quite unusable for eating or chewing, but can be painful, are subject to decay and can cause speech impediments. These teeth are usually removed.
- Peg teeth are conical teeth that are semi-functional. These are the most common kinds of supernumerary teeth, and usually appear in the front, between the incisors.
- An odontoma is a tumour that consists of dental tissues, particularly teeth. These are half formed teeth that can erupt through the skin but usually are contained underneath the gum line.
The appearance of supernumerary teeth is usually genetic in origin, although exposure to certain chemicals and environmental factors, particularly DDT and other insecticides and herbicides during pregnancy has been shown to cause conditions in which supernumerary teeth and odontomas are a condition. If the cause is genetic, it is usually (but by no means always!!!) a part of a larger syndrome, like Gardner’s syndrome, or clediocranial dysostosis. In cases where there are no genetic abnormalities or health conditions, the dentist usually removes supernumerary teeth, although if they do not cause dental problems and are not causing pain or the disfigurement of the patient, then the dentist may opt to keep the tooth or teeth in question.