Supernumeraries

Question 1

What is the definition of a supernumerary?

Answer 1

A tooth or tooth-like structure which develops in addition to the normal series of 32 teeth.

Question 2

What is the incidence of supernumerary teeth?

Answer 2

1-2%

Question 3

What % of midline diastemas are due to supernumerary teeth?

Answer 3

10%

Question 4

What is the aetiology for supernumerary teeth? (give 3 examples)

Answer 4

1. The splitting of the tooth bud in two.
2. Hyperactivity of the dental lamina.
3. Genetic influences.

Question 5

What are the signs that a patient may have a supernumerary tooth?

Answer 5

• Spacing.
• Adjacent teeth failing to erupt.
• Retention of the primary tooth.
• Eruption of the supernumerary tooth.
• Local crowding or irregularity (eg rotation).
• Appearance of extra teeth in the series.

Question 6

Name the 5 types of Supernumerary?

Answer 6

1. Conical
2. Tuberculosis
3. Supplemental
4. Complex odontome
5. Compound odontome

Question 7

Describe a conical supernumerary.

Answer 7

A small peg shaped tooth. The roots are usually well developed and they often erupt. They are known as mesiodens if located in the midline and may cause a midline diastema.

Question 8

Describe a tuberculate supernumerary.

Answer 8

A barrel shaped tooth. They have little or no root and remain unerupted. They are often in pairs and can cause rotations. They can delay or prevent the eruption of central incisors.

Question 9

Describe a supplemental supernumerary.

Answer 9

They have the appearance of an extra tooth or often resemble the adjacent tooth. They are most common in the lower incisor region and are often found at the end of a dental series.

Question 10

Describe a complex odontome.

Answer 10

A disorganised rounded mass of dentine, pulp and enamel.

Question 11

Describe a compound odontome.

Answer 11

A mass of denticles each containing dentine, pulp and enamel.