Knocked-out or broken tooth first aid

Reviewed by Dr. Samar Fadavi, DDS

Short answer: For a knocked-out adult tooth, hold it by the crown, rinse it briefly in milk if dirty, and gently push it back into the socket or keep it in milk, then see a dentist within 30 to 60 minutes. For a broken tooth, save the pieces in milk, rinse the mouth, use a cold compress and call the clinic the same day.

Why quick first aid saves teeth

A tooth is held in its socket by a thin layer of living fibres called the periodontal ligament. When a tooth is knocked out, those fibres stay on the root and begin to dry and die within minutes. Keeping the root moist and getting it back into the socket quickly gives those cells the chance to reattach. That is why a few calm minutes at the scene of a fall or sports injury can decide whether a tooth is kept for many years or lost.

Broken teeth are different. The tooth is still in place, but the break may expose the inner layers or the nerve. Fast care protects the nerve, relieves pain and often allows the dentist to bond the original piece back on.

This guide gives step-by-step first aid for knocked-out, broken, loose and pushed-in teeth in adults and children. It is general information for families in Scarborough, the Danforth and East Toronto. For the wider picture, see our guide on what to do first in a dental emergency, and our emergency dentist page for same-day visits.

First check: is anything more serious going on?

Teeth are usually injured by a fall, a sports collision, a car accident or a blow to the face. Before you focus on the tooth, check the person. Call 911 or go to a hospital emergency department if there is:

• Loss of consciousness, confusion, vomiting or a bad headache after the injury.
• Trouble breathing or swallowing.
• A jaw that looks out of shape, or teeth that no longer meet properly.
• Heavy bleeding that does not slow after 20 minutes of firm pressure.
• A deep cut to the face or lips that gapes open.

Bring the tooth with you in milk. Once the medical problem is managed, the tooth can be treated.

Knocked-out adult tooth: step by step

1. Find the tooth. Look on the ground, in the mouth and in clothing. A whole tooth includes a long root, often longer than the visible crown.
2. Pick it up by the crown. The crown is the white chewing part. Do not touch the root, because the living fibres on it are fragile.
3. Rinse only if it is dirty. Rinse for a few seconds in cold milk or saline. Tap water can be used briefly if nothing else is available. Do not scrub, do not use soap and do not dry it.
4. Try to put it back. If the person is alert and calm, hold the tooth the right way round and gently push it back into the socket with your thumb. It usually slides in with light pressure. Have the person bite gently on a clean cloth or gauze to hold it in place.
5. If you cannot put it back, keep it wet. Place it in a small container of cold milk. Saline or the person’s own saliva in a cup are other choices. An older child or adult can hold it inside the cheek, but only if there is no risk of swallowing it.
6. Get to a dentist fast. Call the clinic on the way. Results are strongest when the tooth is seen within 30 to 60 minutes.

What not to do with a knocked-out tooth

• Do not hold it by the root.
• Do not scrub it, brush it or clean it with alcohol or soap.
• Do not wrap it in a tissue or paper towel; it will dry out.
• Do not store it in plain water for a long time. Water makes the root cells swell and burst.
• Do not let it dry in the air, even for a few minutes.

Knocked-out baby tooth

Baby teeth are never put back into the socket. Pushing a baby tooth back in can damage the adult tooth developing underneath. Instead:

• Have the child bite on clean gauze to stop the bleeding.
• Use a cold compress on the lip if it is swollen.
• Keep the tooth so the dentist can confirm the whole tooth came out.
• Call the clinic the same day so the dentist can check the gum, the bite and the developing teeth.

If you are not sure whether the tooth is a baby tooth or an adult tooth, keep it in milk and call. As a rough guide, the front adult teeth usually come in between about ages 6 and 8. Our children’s dentistry page explains care for young patients.

What the dentist does for a knocked-out tooth

At the clinic, the dentist cleans the area, checks the socket and the tooth and takes x-rays. If the tooth has not been put back yet, it is gently rinsed and replanted. It is then held in place with a thin flexible splint bonded to the neighbouring teeth for about two weeks. A tooth that was out of the mouth for a long time may need a longer splint.

Most adult teeth that are knocked out will need root canal treatment, often started within a week or two, because the nerve inside usually does not survive. The dentist will also check whether your tetanus protection is up to date and may suggest a short course of antibiotics. Regular follow-up visits and x-rays over the next months and years watch for changes in the root.

Broken or chipped tooth

Broken teeth range from a tiny chip on the edge to a break that splits the tooth. First aid is similar for all of them:

1. Rinse the mouth gently with warm water.
2. Find and save any pieces in a small container of milk or water. The dentist may be able to bond the original piece back on.
3. Press clean gauze on any bleeding for 10 to 15 minutes.
4. Hold a cold compress on the cheek or lip to reduce swelling.
5. Cover a sharp edge with orthodontic wax or sugarless gum to protect the tongue and cheek.
6. Take over-the-counter pain medicine as directed on the package if needed.
7. Call the clinic. Describe how large the break is and whether you see pink or red in the centre.

How serious is the break?

• Small chip in the enamel: No pain, rough edge. Can usually be smoothed or bonded at the next available appointment.
• Break into the dentin: A yellowish layer shows and the tooth is sensitive to cold and air. Needs care within a day or so to seal the tooth.
• Break that exposes the nerve: A pink or red dot or bleeding in the centre of the tooth, with sharp pain. Needs same-day care to protect the nerve.
• Break below the gum or split down the root: The tooth may move in pieces. Needs same-day assessment; some of these teeth cannot be saved.

How a broken tooth is repaired

Treatment depends on the size and depth of the break. Small chips are smoothed or rebuilt with tooth-coloured bonding. Larger breaks may need a filling, an onlay or a crown. If the nerve is exposed or damaged, the tooth may need a root canal first. Our crowns and bridges page explains how crowns protect a weakened tooth, and our guide on what happens during a root canal explains that treatment step by step.

Loose tooth after an injury

A blow can loosen an adult tooth without knocking it out. Do not wiggle it to test it. Have the person bite gently on a soft cloth, use a cold compress and eat soft foods. See the dentist the same day. A loose tooth often needs a splint for a few weeks so the supporting fibres can heal, and the nerve is checked over the following months.

Tooth pushed out of place

Sometimes a tooth is pushed forward, backward, sideways, partly out of the socket or up into the gum. If it is only slightly out of position and the person is comfortable, you can try to guide it back with very light finger pressure. Do not force it. Bite on a cloth and come in the same day. A tooth pushed up into the gum, especially a baby tooth, should be left alone for the dentist to assess.

Injuries to the lips, tongue and gums

Mouth injuries bleed a lot because the area has a rich blood supply. Rinse gently, then press clean gauze on the cut for 15 to 20 minutes. A cold compress helps with swelling. A cut through the lip border, a deep tongue cut or a wound that keeps bleeding may need stitches. Check for small tooth fragments inside a lip cut; the dentist may take an x-ray of the lip if a piece is missing.

Helping children through a tooth injury

Children can be frightened by blood and by the adults around them. A calm voice and simple words help. Tell them what you are doing before you do it. Offer a cold treat such as a frozen yogurt tube for comfort and swelling once bleeding has stopped. After the visit, watch for changes in the injured tooth over the following weeks, such as a grey colour, swelling or a small bump on the gum, and tell the dentist if you see them.

Preventing knocked-out and broken teeth

• Wear a well-fitted mouthguard for hockey, soccer, basketball, rugby, martial arts, skateboarding and cycling tricks.
• Use car seats, booster seats and seat belts every trip.
• Use stair gates and keep floors clear for toddlers.
• Do not chew ice, popcorn kernels, hard candy or pens.
• Do not open bottles or packages with your teeth.
• Wear a night guard if you grind your teeth, since grinding weakens teeth and makes them easier to break.
• Treat large old fillings and cracks before the tooth breaks. Regular check-ups help catch weak spots early.

Mouthguards for sports

A mouthguard spreads the force of a blow across the teeth and jaw and cushions the lips. Store-bought boil-and-bite guards are better than nothing, but a custom guard made from a model of your teeth fits more closely, stays in place and is easier to breathe and talk with. Bring your guard to check-ups so the fit can be checked as children grow.

Keep a tooth rescue kit ready

For families with active kids or adults who play contact sports, a small kit in the sports bag helps:

• A small container with a lid.
• A small carton of shelf-stable milk or a bottle of saline.
• Clean gauze and a cold pack.
• Orthodontic wax.
• The clinic number: (647) 350-4500.

When to see a dentist

Call the clinic right away if:

• An adult tooth is knocked out, loose, pushed out of place or pushed into the gum.
• A tooth is broken and you see pink, red or bleeding in the centre.
• A broken tooth is painful, sensitive or has a sharp edge you cannot cover.
• A baby tooth is knocked out or injured.
• A tooth that was injured weeks ago turns grey, becomes painful or has a bump on the gum.

Our emergency dentist page explains same-day visits. You do not need to be an existing patient.

Questions about knocked-out and broken teeth

Can a knocked-out tooth really be saved?

Often, yes, especially when it is put back or kept in milk and seen by a dentist within 30 to 60 minutes. The longer the root is dry, the lower the chance it heals well.

Why milk and not water?

Milk is closer to the body’s own fluids, so it keeps the root cells alive longer. Water makes the cells swell and break.

Should I put a baby tooth back in?

No. Replanting a baby tooth can harm the adult tooth underneath. Keep the tooth and call the clinic.

Will a replanted tooth need a root canal?

Most adult teeth that were fully knocked out need root canal treatment within a few weeks. In young children with roots that are still growing, the dentist may wait and watch.

Can a chipped tooth be fixed so it looks natural?

Yes. Small chips are usually rebuilt with tooth-coloured bonding that is matched to the shade of your teeth. Larger breaks may need a crown or veneer.

My tooth turned grey after a fall. Is that a problem?

A grey tooth after an injury can mean the nerve is damaged. Book a visit so the dentist can check it with an x-ray.

Is a knocked-out tooth covered by insurance or CDCP?

Many plans include emergency and restorative care, but coverage depends on your plan. The team can help you check, and you will receive a written estimate before planned treatment.

Related guides

• Replacing a front tooth: your options
• Cracked tooth: symptoms and treatment
• Implants, bridges or dentures?