Supernumerary Teeth

When I look at a dental x-ray sometimes I see where a permanent tooth is missing and never came in, and with others I see more than the normal 32 teeth. The extra teeth are known as supernumerary teeth. According to Wikipedia, they can appear anywhere in the dental arch.

These teeth are usually classified by their shape: supplemental (normal shape), tuberculate (barrel shaped) or cone shaped (peg shaped). There is also tooth matter – some teeth are less-well formed. This is known as an odontoma. Of these, the most common is the peg-shaped tooth which comes in between the 2 maxillary central incisors.

What are the main causes?

At the top of the list is genetics. I have seen the same anomaly occur from generation to generation – for example, the presence of a fourth molar (an extra wisdom tooth). This can also be part of an inherited syndrome, such as Gardner’s syndrome, where extra teeth are one of the telling signs .

 What problems can occur from extra teeth?

  1. The supernumerary tooth can get in the way of the permanent teeth erupting.
  2. There can be an esthetic problem because there should be only 4 incisors and 2 canines in each arch, and an extra tooth can throw off the symmetry or just not look right.
  3. It can cause crowding.
  4. There can be pathology in these forming teeth.

How common is supernumerary teeth?

According to a study done in 1999 and referenced by the Canadian Dental association, supernumerary teeth are found in 2.1% of the population, and at a higher rate in patients with abnormalities such as cleft palate and cleidocranial dysplasia.

On a personal note, I had 2 supernumerary teeth in my upper premolar areas. They were both removed prior to having braces placed when I was 12 years old. Each case has to be examined for the best treatment for that patient.