🌱 WISDOM & ERUPTION

Supernumerary Tooth

Korean: 과잉치 · 한국어 설명 보기

Also called: extra tooth · supernumerary teeth · hyperdontia · mesiodens · extra tooth in gum

In short

A supernumerary tooth is an extra tooth beyond the normal count of 20 primary or 32 permanent teeth. The most common type is a mesiodens, sitting between the two upper front teeth, and it is usually found on a routine childhood radiograph before it causes any complaint. It matters because it can block or deflect the permanent incisors, and early detection generally means simpler treatment.

Where extra teeth appear

TypeLocationRelative frequency
MesiodensBetween the upper central incisorsMost common
DistomolarBehind the third molarCommon
ParamolarBeside a molar, toward the cheekUncommon
Supplemental incisor or premolarA duplicate of a normal toothUncommon

Extra teeth occur more often in the upper jaw than the lower and more often in boys than girls. Many are shaped abnormally — small, cone-shaped, or peg-like — which is one reason a supernumerary is often recognisable on a radiograph even before its position is clear.

Why it is usually discovered by imaging rather than by symptoms

A supernumerary tooth commonly stays buried, and buried teeth do not hurt. The situation that brings families in is a permanent front tooth that has not arrived while its counterpart on the other side erupted months earlier, or two front teeth that came in visibly rotated or splayed apart. In both cases the underlying cause may be an extra tooth sitting in the eruption path. This is a substantial part of the argument for taking a screening radiograph around the time the permanent incisors are due.

Problems an untreated supernumerary can cause

  • Failure of eruption — the permanent incisor is physically obstructed and becomes an impacted tooth.
  • Deflection — the tooth erupts but in the wrong position or angle, producing malocclusion that then needs correction.
  • Crowding and midline shift — the extra width has to go somewhere.
  • Root resorption of the adjacent permanent tooth from sustained pressure.
  • Cyst formation in the follicle around the buried extra tooth.
  • Plaque trap if it does erupt, since an oddly placed tooth is difficult to clean and invites gingivitis and decay.

How the decision is made

  1. Remove it when it is blocking or deflecting a permanent tooth, resorbing a neighbouring root, associated with a cyst, or creating an uncleanable position. Timing is chosen to protect the developing roots of the neighbouring teeth, so this is a judgement about the child's stage of development rather than simply their age.
  2. Monitor it when it is deeply buried, causing no obstruction, and has no cyst — with periodic imaging rather than assumption.
  3. Keep it in the occasional case where a supplemental tooth is well aligned, functional, and cleanable, or where it can substitute for a genuinely missing tooth.

Removal is frequently only the first half of the plan. Once the obstruction is cleared, the delayed incisor often needs orthodontic guidance into position, so the surgical and orthodontic phases are planned together rather than sequentially by accident.

Associated conditions worth knowing about

Isolated supernumerary teeth are the norm, but multiple extra teeth can be associated with syndromes such as cleidocranial dysplasia or Gardner syndrome, and extra teeth are also more common in cleft lip and palate. Finding several extras is therefore a reason for a broader assessment, not just a dental one. A single mesiodens, by contrast, is usually an isolated finding with no systemic implication.

Notes for families based in Korea

If your child is around seven or eight and one upper front tooth has not appeared while the other has, ask for a radiograph rather than waiting another year. Detected early, the usual outcome is one small surgical procedure and a straightforward orthodontic phase; detected after the incisor is fully impacted and the neighbours have closed the space, treatment becomes considerably longer. We are about 30 minutes from Camp Humphreys, consultations are in English, and we provide copies of imaging and a written treatment summary so care can continue elsewhere after a PCS. Book an assessment.

Frequently asked questions

How do I know if my child has an extra tooth?

Usually you do not, because most stay buried and buried teeth are painless. The visible clues are a permanent front tooth that has not arrived while its opposite number erupted months earlier, or front teeth that come in rotated or unusually far apart. Confirmation requires a radiograph, which is one reason a screening film around the time the permanent incisors are due is worthwhile.

What is a mesiodens?

A mesiodens is the most common supernumerary tooth, sitting in the midline between the two upper central incisors. It is often small and cone-shaped and frequently remains buried. Its significance is positional: it lies exactly in the eruption path of the permanent front teeth, so it can block or deflect them, which is why it is usually removed once identified.

Does an extra tooth always need to be removed?

No. Removal is indicated when it is obstructing or deflecting a permanent tooth, resorbing an adjacent root, associated with a cyst, or sitting somewhere that cannot be cleaned. A deeply buried extra tooth causing none of these can reasonably be monitored with periodic imaging, and occasionally a well-aligned supplemental tooth is simply kept as a functional tooth.

When is the best time to remove one?

The timing is chosen around the development of the neighbouring permanent teeth, so that surgery does not damage their forming roots, rather than at a fixed age. In practice this often means the mixed-dentition years. Waiting too long is the greater risk, because once the blocked incisor is fully impacted and the neighbours have drifted into its space, treatment becomes longer and more complex.

Will my child need braces afterwards?

Frequently yes. Removing the obstruction clears the path but does not by itself bring a delayed incisor into position, and any deflection or space loss that already occurred still needs correcting. For this reason the surgical and orthodontic phases are best planned together from the outset, which also gives you a realistic picture of the overall timeline.

Are extra teeth hereditary?

There is a familial tendency, and they occur more often in boys and more often in the upper jaw. A single extra tooth is usually an isolated finding with no wider implication. Multiple supernumerary teeth are different: they can be associated with conditions such as cleidocranial dysplasia or Gardner syndrome, so that finding warrants a broader medical assessment rather than a purely dental one.

Related terms

Have this checked in English

Consultation with panoramic X-ray and 3D CT included, explained in English before anything starts. About 30 minutes from Camp Humphreys · open 365 days a year.

Browse the dictionary