What is it?
Dental trauma is the shared name for the damage caused by a sudden blow to a tooth and to the tissues around it. It covers a wide range, from a small chip in the enamel to a tooth coming right out of its socket. The same blow may also have injured the lip, the tongue, the gum, the ligament that attaches the tooth to the bone, and the jawbone.
The damage you can see is often not all of the damage. Even when the tooth is still in place and still whole, the ligament around the root may have been crushed and the bundle of blood vessels and nerve entering the tooth may have been stretched. So having no pain after a blow does not mean an examination is unnecessary; some of the consequences of an injury only show up weeks, or even months, later.
With this kind of injury, time counts for as much as the treatment. When an adult tooth comes right out, the cells on the root surface stay alive for a matter of minutes, and every minute the tooth spends drying outside the mouth lowers the chance of it taking hold again once it is put back. Baby teeth are judged differently; because of the risk of harming the developing adult tooth underneath, putting them back is usually not considered appropriate.
Signs
You will not necessarily have all of these at once.
Why does it happen?
- 01
Falls and knocks
Falling is the commonest cause of injury to the face. In toddlers just learning to walk, during play, and in later life when balance is lost, the blow usually lands on the upper front teeth, because these teeth sit at the very front of the arch where the lip protects them least.
- 02
Sport and anything with wheels
Contact sports, martial arts and accidents on bicycles, skateboards and scooters carry a clear risk. In these accidents a broken tooth may come with an injury to the lip; the broken-off piece of tooth sometimes stays inside the lip tissue, and that is looked for separately.
- 03
Road accidents, accidents at work and heavy blows
In high-energy injuries the damage is not limited to a single tooth. Fractures and displacement in several teeth, a break in the jawbone and a bite that no longer meets properly can all be seen together. With these injuries, the possibility of a head injury and of a broken jaw is assessed first.
- 04
Things that leave a tooth open to breaking
Teeth with a large filling, with advanced decay or with a root canal treatment behind them can break even with a small knock. Front teeth that stick noticeably forward, and lips that do not fully cover the teeth, also make it easier for a blow to land straight on the tooth.
How does it progress?
- Fracture
The tooth tissue breaks
The most superficial form is a break in the enamel; a small chip is left in the tooth and it usually causes no pain. Once the break reaches the dentine, a sharp sensitivity to heat, cold and air begins. When the break opens into the pulp, the blood vessel and nerve tissue inside the tooth, a pink or red spot can be seen on the broken surface. A break can also lie below the gum, in the root; that can only be made out on an X-ray.
- Displacement
The tooth is still there but shaken or shifted
With a shaking injury the tooth does not move, it is only tender to touch and to biting. When it has been loosened, the tooth moves and there may be bleeding from the gum margin. The tooth may have been pushed part of the way out of its socket, shifted sideways, or driven up into the bone. What these all have in common is a change in the bite: if your teeth no longer meet the way they used to, the tooth may have moved.
- Knocked out
The tooth comes right out of its socket
This picture, called avulsion, is the one in which time matters most for an adult tooth. On the root surface there are living cells that attach the tooth to the bone; once these cells dry out, the chance of the tooth taking hold again falls. How long the tooth spends outside the mouth, and how it is kept during that time, are the two things that count even before the treatment itself.
- Baby tooth
Injury to a baby tooth in a child
When a baby tooth is injured, the real question is not the tooth itself but the adult tooth developing right underneath it. For that reason a baby tooth that has come out is not put back, and where a baby tooth has been driven into the bone, watchful monitoring comes first. The effect of the blow may show up years later as a change in the colour or the shape of the adult tooth; this is why the child is asked back for check-ups at intervals over many months.
How is it treated?
What is done in the first few minutes is part of the treatment. Hold an adult tooth that has been knocked out only by the crown, the part that shows in the mouth; do not rub the root surface, do not brush it and do not wipe it with a tissue. If the tooth is dirty it can be rinsed for a few seconds in milk or in saline. Where possible the tooth is eased gently back into its own socket and held there with light pressure through a clean cloth. If that cannot be done, the tooth is kept in milk, in saline or in the person's own saliva; leaving it in tap water damages the cells on the root surface. After that, see a dentist without delay.
At the clinic the extent of the injury is worked out first. How much the teeth move, the bite, the soft tissues and the jawbone are all assessed; X-rays are taken where they are needed, and with lip injuries it is checked whether a broken-off piece has stayed in the tissue. Teeth that have moved can be brought back into position and held for a time with a flexible splint attached to the neighbouring teeth. Where a tooth has broken, the missing tissue can be built up with filling material, and if the broken-off piece has been kept it can in some cases be bonded back in its own place. If the break has reached the pulp, covering the pulp, removing part of it or root canal treatment comes into question. You will also be asked about your tetanus vaccination.
An injured tooth is not a job that closes in a single appointment. At the check-ups, whether the tooth is still alive, its colour, how much it moves and the bone around the root are assessed at set intervals; this monitoring is often measured in months and in some cases in a few years. After a blow, the nerve tissue inside the tooth may die, the tooth may darken, or the root may start to break down. When these are picked up early, the choices for dealing with them are wider; this is why you are asked not to skip the check-up appointments even if your symptoms have passed.
- If an adult tooth has come right out of its socket; with this, minutes change the outcome
- If a tooth has been driven into the bone, has shifted sideways, or your teeth no longer meet the way they used to after the blow
- If there is a pink or red spot on the broken surface, or bleeding that seeps from it
- If after the blow there is fainting, vomiting, blurred vision, or bleeding from the ear or nose; with this, the first place to go is an emergency department
How is it prevented?
- Wear a mouthguard for contact sports and martial arts; one made to fit you from an impression stays in place better, but a ready-made mouthguard is still better than none at all.
- Wear a helmet when cycling, skateboarding or riding a scooter; for children, models with a chin bar also keep the front teeth out of the path of a blow.
- Use a seatbelt in the car, and an age-appropriate child car seat, on every journey; at home, cut down on the causes of falls such as slippery floors, cluttered stairs and poor lighting.
- In children whose front teeth stick noticeably forward and whose lips do not cover their teeth, the risk of injury is one of the things discussed at an orthodontic assessment.
Frequently asked questions
- What should I bring a knocked-out tooth in?
- The tooth can travel in milk, in saline or in the person's own saliva; where possible, putting the tooth back into its own socket and coming in like that is preferred. Tap water is not suitable, it damages the cells on the root surface. Do not rub the root or scrape the tissue off it. Because baby teeth are not put back, the step of placing the tooth into the socket is not expected in children; even so, bring the tooth that came out with you.
- My tooth is still in place and I have no pain; do I still need an examination?
- You do. At the moment of the blow the blood vessel and nerve entering the tooth may have been injured, and the signs of that may not appear straight away. At the first examination the state of the tooth on that day is recorded; at later check-ups any change in colour, loss of vitality or change in the root is judged by comparing it with that record. Without a starting record to compare against, it becomes harder to tell apart problems that appear late.
- I kept the broken-off piece; can it be used?
- With some fractures the broken-off piece can be bonded back into its own place. What matters is that it does not dry out; bring it in milk or saline, in a closed container. If the piece does not fit, or has come away in very small fragments, the missing tissue can be built up with filling material. Bringing the piece does not mean it will be bonded back in every case; the decision is made according to where the break is, how far it goes and the state of the pulp.
This content is for general information and does not replace an in-person examination. Symptoms overlap between conditions, and a diagnosis can only be made clinically.