Congenitally missing teeth: when and how is the gap filled?

A congenitally missing tooth is not a tooth that has been lost later; the bud of that tooth never formed. In dentistry this is called hypodontia. Most people are missing only one or two teeth. The severe forms in which many teeth are missing are called oligodontia, and the very rare condition in which all the teeth are missing is called anodontia. Missing wisdom teeth, on the other hand, are very common and usually need no treatment; this page is about the other teeth.

The teeth most often missing are the second premolars, especially the lower ones, and the upper lateral incisors right next to the two front teeth. It is reported to be slightly more common in girls. A missing tooth often comes with small or pointed teeth; a lateral incisor missing completely on one side and staying small on the other is a pattern that is seen.

The cause is usually genetic, and it can be seen in other members of the family; however, not everyone with congenitally missing teeth passes it on to their child. It mostly occurs on its own, without any other health problem. It is more common, though, in cleft lip and palate, Down's syndrome and ectodermal dysplasia. If many teeth are missing and this comes with differences in the hair, nails or sweating, an assessment for a syndrome is carried out.

It is usually noticed while the baby teeth are being replaced: a baby tooth does not fall out, or falls out but no new tooth comes through in its place, or a tooth that should be symmetrical on both sides is missing on one side. A definite diagnosis is made with an examination and an X-ray. Because some tooth buds, especially second premolars, can appear late, what is seen on an X-ray taken very early should be interpreted by a dentist and monitored if necessary.

Where a permanent tooth is missing, the baby tooth often stays in the mouth, because there is no permanent tooth to dissolve its roots and take its place. A healthy baby tooth can go on working like this for years, sometimes for twenty years or more. Some baby molars, however, gradually start to sit below the chewing level of the neighbouring teeth; in dentistry this is called infraocclusion, and it needs to be monitored.

Not every congenitally missing tooth needs treatment. If the gap does not show, does not affect chewing and does not bother you, monitoring is an option too. When treatment is needed, the decision is usually made not by a single dentist but jointly by an orthodontist and a restorative dentist. The first and most important decision is whether the gap should be closed, or opened to the right width and filled with a tooth; every step after that follows from it.

The breakdown below focuses on the implant decision, because this is the question both families and young adults ask most often. Braces, bridges and dentures are covered further down.

Treatment for congenitally missing teeth can stretch over years. Although the order varies from person to person, the backbone of most plans looks like this.

1. 1

   Examination and X-rays

   A panoramic X-ray shows which teeth are missing, the condition of the baby teeth and how the other teeth are developing. The diagnosis is confirmed at this stage.

2. 2

   Family and medical history

   You are asked whether anyone in the family has similar missing teeth, about any history of cleft lip and palate, and about differences in hair, nails or sweating. If many teeth are missing, further assessment is planned.

3. 3

   The decision about the gap

   The orthodontist and the restorative dentist decide together whether closing the gap or opening it and filling it is the better choice. The bite, the facial profile, and the position and number of missing teeth determine this decision.

4. 4

   Braces

   Braces usually start after most of the permanent teeth have come through, and often take a few years. The aim is to close the gap, or to open a space of the right width in the right place for the tooth that will fill it.

5. 5

   Retainer and temporary tooth

   After the braces come off, a retainer is used to stop the teeth moving back. If growth has not yet finished, the gap is closed temporarily during this period with a retainer carrying an artificial tooth, a small removable denture or a resin-bonded bridge.

6. 6

   Permanent replacement

   Once the teeth have settled, the gap is filled with a resin-bonded bridge, a conventional bridge or a denture; or, if growth is complete and there is enough bone, with an implant.

7. 7

   Long-term follow-up

   When treatment ends, regular check-ups continue with your own dentist. How the retainer is being worn, the wing of the bridge, the gum around the implant and any baby teeth still in the mouth are monitored at these check-ups.

None of them is right on its own for every mouth. The choice depends on the position and number of missing teeth, the state of the neighbouring teeth and age.

These are the possible consequences of both waiting and rushing. None of them is inevitable; most can be prevented with the right timing and regular follow-up.

The first few weeks differ depending on the route chosen. What they all have in common is that retention, which keeps the teeth in position, and regular check-ups continue.

1. After a resin-bonded bridge

   The bridge can be used the same day. Avoid biting very hard things with the bridged tooth and putting strain on the wing. Clean between the teeth and around the wing every day.

2. After an implant

   Mild swelling and tenderness in the first few days are normal. With a single-tooth implant, a temporary tooth is used throughout the fusion period; the permanent crown is fitted once this period is over.

3. The retainer

   After braces, the retainer should be worn for as long and as often as your orthodontist recommends. Because teeth tend to keep moving over the years, this often continues for a long time.

4. Regular check-ups

   The wing of the bridge, the gum around the implant, how the implant tooth lines up with its neighbours and any baby teeth still in the mouth are monitored at check-ups.

Treatment for congenitally missing teeth is not a single procedure but a series of stages that follow one another. These are the main items that determine the scope:

Number and position of missing teeth

A single missing lateral incisor and a mouth with many missing teeth call for very different plans.

Whether braces are needed

If braces are needed to close or open the gap, the plan stretches over years.

How long the temporary solution is needed

If you are waiting for growth to finish, how long the temporary tooth will be used and how many times it will be renewed affect the plan.

The type of permanent replacement

A resin-bonded bridge, a conventional bridge, a denture and an implant involve different stages; with an implant, the width of the bone and, if needed, adding bone also determine the scope.