Intrusion

Adult Teeth and Dental Trauma

In this section, we will cover:

What is an intrusion?
What should I do after the injury?
Will I need treatment?
What can I do to help the area heal at home?
Will I need any follow up appointments?
What should I look out for?
What are the long term complications?

What is an intrusion?

An intrusion is an injury to the structures supporting the tooth after which the tooth is:

pushed further into the socket so it looks shorter than before the injury
not wobbly

What should I do after the injury?

It can be very distressing if you or your child has suffered trauma to the teeth. The first thing to do is not panic.

Dental trauma is very common and there are a few steps you can follow to get the best outcome after the injury.

You should:

Take a second to collect yourself and check you/your child hasn't blacked out.
If you/your child has hit their head and you think they may have lost consciousness (even for a few seconds) or they feel nauseous or dizzy, you should get this checked out by your doctor or local A&E department to rule out a concussion (head injury)
Call your dentist as soon as possible so they can arrange to check the teeth and provide any necessary treatment.
If there are any cuts in or around the mouth, clean them with warm salty water. If there is any bleeding, dampen a clean handkerchief in salt water and press it firmly on the bleeding area.
If the injury happened in a place thought to be unclean, and there has been a cut to the skin/lip/gum, you should check all tetanus vaccinations are up to date with your GP. You may need a tetanus booster vaccination.

Will I need treatment?

Your dentist will take some xrays to check there are no other injuries to the teeth and to compare any future xrays against.

Treatment depends on whether the root is fully formed. Root formation is usually completed 3 years after the tooth erupts.

Root not fully formed

Tooth should be left to naturally re-erupt
If this does not happen within 4 weeks, orthodontic treatment (braces) can be started to bring the tooth in line with the rest of the teeth

If the root has not fully formed, the tooth should be closely monitored for signs of infection/complications (see below). If an infection develops, root canal treatment should be started as soon as possible.

Root fully formed

The treatment needed depends on how far the tooth has been pushed into the socket.

If less than 3mm, the tooth can be left to naturally re-erupt. If this does not happen within 8 weeks, the tooth will have to be repositioned:
- surgically (then secured with a splint - flexible metal wire - for 4 weeks)
- or orthodontically (with braces)
If between 3 to 7mm, the tooth will have to be repositioned surgically or orthodontically
If more than 7mm, the tooth will have to be repositioned surgically

For all teeth where the root has fully formed, root canal treatment should be started 2 weeks after the injury to prevent inflammatory root resorption (see below).

If there are any injuries to the soft tissue, you can see here for more information.

What can I do to help the area heal at home?

To help the area heal at home, you should:

Brush the teeth after every meal with a soft toothbrush
Gently brush the injured area to prevent build up of plaque
Carry out salt water or alcohol-free chlorhexidine mouthwash (corsodyl) twice a day.
For a young child who isn't able to use a mouthwash, use a cotton swab/handkerchief moistened in salt water or alcohol-free chlorhexidine mouthwash (Corsodyl) to clean the gum twice a day
Have a soft diet
Take medicine to help manage any discomfort (ibuprofen or paracetamol)
Avoid contact sports
Don't smoke

Will I need any follow up appointments?

Your dentist will want to see you/your child again for a clinical examination and xray after:

2 weeks (for a mature tooth, root canal treatment will be started here)
4 weeks (the splint will be removed at this appointment)
8 weeks
12 weeks
6 months
1 year
every year for 5 years

X-rays are taken to assess how the root of the tooth is developing and to identify any complications with healing.

What should I look out for?

The long term consequences of dental trauma are unpredictable. You should monitor your/your child's teeth for any signs of infection.

Favourable outcome

No pain
Normal colour of the tooth
Temporary darkening of the tooth to red/grey/yellow
Tooth back to normal position or is re-erupting

Unfavourable outcome

Pain
Abscess on the gum
Increased mobility
Permanent grey discolouration of the tooth, along with one of the above signs/symptoms
Tooth not moving in line with rest of teeth

What are the long term complications?

The long term consequences of dental trauma are unpredictable. You should monitor your/your child's teeth for any signs of infection (see "unfavourable outcome" above).

If an adult tooth has been injured, possible long term complications include:

1) Nerve damage

A) Nerve dies causing pain and infection.
The tooth may look grey/brown and be tender to bite on. This can be managed with root canal treatment. Once the tooth has been treated, it can be whitened to improve the appearance. You can find about more about tooth whitening here.
B) Root canal constricts as more dentine is formed (find out more about tooth anatomy here).
This is called "pulp canal obliteration". The tooth may look more yellow or brown but you won't have any pain from the tooth. This doesn't need any treatment unless the nerve dies. If the nerve dies, you may need to see a specialist endodontist for root canal treatment. If you are unhappy with the colour of the tooth, you can consider a course of tooth whitening.
C) Tooth starts to "dissolve" from the inside out.
This is called "internal inflammatory resorption". The tooth may have a pink-ish tinge to it. In most cases, you won't have any pain from the tooth unless the resorption has extended to the outer surface of the root. If detected very early, this condition can usually be managed with root canal treatment. Sometimes, the tooth will have to be removed (see dental extraction).

2) Damage to outer surface of root

A) Outer surface of the root starts to "dissolve" away due to infection.
This is called "external inflammatory root resorption". Root canal treatment should be started immediately to try to stop it progressing. Your dentist may refer you to a specialist children's dentist (paediatric dentist) or root canal specialist (endodontist) to continue treatment.
B) Outer surface of the root is replaced by, and fuses to, the surrounding bone.
This is called "external replacement resorption" or "ankylosis" and is most common when the tooth has been completely knocked out of the mouth. In a growing child, the damaged tooth will start to look shorter than the surrounding teeth. This is called infraocclusion (i.e. below the line of bite). You can find out more about it here - LINK avulsion.

3) Abnormal root development

This is more relevant if the injured tooth has erupted in the last 3 years, as the root is still forming under the gum.
If the nerve dies, the root stops growing.
This means the tip of the root is left wide open. It can be managed with root canal treatment and a special material called "MTA", which is a bit like a cement. MTA is used to "plug" the hole at the tip of the root during root canal treatment. This is a treatment which is usually only carried out by a specialist children's dentist (paediatric dentist) or endodontist (root canal specialist).