Key points in brief
- A baby tooth abscess does not heal on its own, even after the pus drains and the pain stops. The infection can reach the permanent tooth below, so the tooth needs root canal treatment or removal.
- The tooth is usually treated if it can be rebuilt with a tight seal and will not fall out for a long time. A badly damaged tooth, or one with infection near the permanent tooth, is usually removed.
- Without facial swelling or fever, show a pus-filled bump to a dentist within a few days, and a swollen gum within 24 hours. Do not pierce or squeeze the bump, and do not warm the cheek.
- Swelling of the cheek, around the eye or under the jaw, fever, weakness, difficulty opening the mouth or refusing to drink need help the same day, at a hospital emergency department (SOR) if the practice is closed.
- If the swelling grows quickly, closes the eye or your child is getting worse, go straight to a hospital emergency department. If breathing or swallowing is difficult, call 112.
Consult your case with an expert and get your treatment plan
Why a baby tooth abscess may not hurt
A baby tooth abscess may not hurt because the pus has found a way out onto the gum, or because the nerve inside the tooth has already died. It usually starts with untreated tooth decay, less often with an injury. Bacteria reach the pulp, that is the nerve and blood vessels inside the tooth, and the pulp dies. The infection then spreads from the canals inside the roots to the bone around them.
When the pus has no way out, it collects under the gum and pushes the tissues apart. The gum next to the tooth swells, the tooth hurts when your child bites, and the swelling may spread to the cheek. This kind of abscess is an acute condition.
When the pus breaks through the bone, a bump or a small pimple appears on the gum next to the tooth, and fluid oozes from it. This is a sinus tract, a channel through which pus drains from the bone onto the gum. It usually means a chronic condition, in which the infection carries on quietly. With a baby tooth, a dental sinus tract on the gum behaves just as it does in adults: it can close up and then open again a few days later.
A young child often cannot say what is wrong. A parent is then more likely to notice a bump on the gum, bad breath, a greyish or darker tooth - especially after a knock - or that the child chews on one side only.
The tooth behind the last baby tooth is easy to mistake for a baby tooth, but it is already the six-year molar, the first permanent back tooth. An abscess on the six-year molar is a tooth abscess in a permanent tooth, and it can often be cured with root canal treatment.
A baby tooth abscess can burst on its own and the pus can drain through the gum, but pus draining away does not mean the infection has healed. The infection only clears once the dentist has cleaned the canals or taken the tooth out.
When your child cannot wait until morning
Your child needs to see a doctor the same day when the infection spreads beyond the tooth. The European Academy of Paediatric Dentistry lists the signs that show this:
- swelling of the cheek, around the eye or under the jaw, especially if it is getting bigger,
- a fever,
- noticeable weakness or drowsiness,
- difficulty opening the mouth,
- refusing to drink, or signs of dehydration such as a dry mouth and fewer wet nappies than usual.
If your child has any of these signs and the practice is closed, go straight to a hospital emergency department (SOR). Go straight there as well if the swelling grows quickly, closes the eye, or your child is getting worse. If your child has difficulty breathing or swallowing saliva, call 112.
Infection spreading like this to the cheek, the area around the eye or the neck is rare. A swollen gum in a child or severe toothache, without facial swelling and without a fever, is a reason to have your child seen by a dentist within 24 hours. Show a painless pus-filled bump to a dentist within a few days, sooner than you would for an adult, because a permanent tooth is growing beneath the baby tooth. Do not wait for it to close, because a closed sinus tract does not mean the infection has gone.
A child with a heart defect, diabetes, a weakened immune system or another long-term illness needs to be assessed sooner. In that case, call the practice the same day about any abscess, and tell them about the illness and the medicines your child takes.
Should the baby tooth be treated or taken out?
A baby tooth with an abscess needs either root canal treatment or removal. The dentist decides which way to go after an examination and an X-ray, by answering several questions in turn. One of them concerns the roots, which in a baby tooth dissolve by themselves as the time for the tooth to fall out gets closer.
| The dentist's question | If yes | If no |
|---|---|---|
| Has the infection spread beyond the tooth: facial swelling, fever, feeling unwell? | help the same day: the dentist cleans the canals or removes the tooth, and sometimes gives an antibiotic or refers your child to hospital. If the tooth stays, next question | next question |
| Can the crown of the tooth, the part you see in the mouth, be rebuilt with a tight seal? | next question | removal of the tooth |
| Are the roots still long, with plenty of time left before the tooth is due to fall out? | next question | usually removal of the tooth |
| Is the developing permanent tooth, growing beneath the baby tooth, clear of the infection? | next question | usually removal of the tooth |
| Will your child cope with treatment with a local anaesthetic, and does their general health allow it? | root canal treatment of the baby tooth, and check-ups | removal. If the only obstacle is that your child will not cope with the procedure, also treatment under sedation (after a calming medicine) or under general anaesthesia |
When the dentist gives a baby tooth root canal treatment, they first numb it with a local anaesthetic, then clean and disinfect the canals, and finally fill them with a paste. This paste usually dissolves, although not always at the same rate as the root. The treatment takes one visit or several.
A treated tooth usually stays in the mouth until it falls out naturally, and it holds the space for the permanent tooth. In young children, root canal treatment is often a good option, but the tooth then needs check-ups, including X-rays. Some observations suggest that in molars with a sinus tract the treatment fails more often, so check-ups matter especially in that case.
With an abscess, partial treatment is not enough. In this treatment, the dentist removes only the pulp from the crown of the tooth (a pulpotomy). It is used in teeth with living pulp, without a sinus tract or swelling.
What to do about an abscess on your child's gum until the appointment
Pus on a child's gum only stops collecting once the tooth has been treated or removed, because its source is in the tooth's canals. Mouthwashes, ointments and home compresses on the gum do not reach that far. Until the appointment, do not pierce the bump or squeeze pus out of it. Squeezing can push the infection deeper into the tissues. Do not put a hot-water bottle or warm compresses on the cheek, because warmth encourages the infection to spread. A cool compress on the outside of the cheek, wrapped in a cloth, may bring some relief.
Brush your child's teeth as usual, gently around the affected tooth. Give soft food and make sure your child drinks. Write down when the bump first appeared, whether your child has had a fever and whether anything hurt - this makes it easier for the dentist to judge how long the infection has been going on.
Keep an eye on your child, at night too. If cheek swelling, a fever or weakness appears, or your child stops drinking, do not wait for the booked appointment, and get help the same day.
Do not give an antibiotic from your home medicine cabinet. An antibiotic does not remove the cause, and given when it is not needed it may make later treatment harder. Talk to a doctor or a pharmacist about a painkiller and the right dose for your child, and do not put a tablet on the gum.
How an infected baby tooth affects the bone and the permanent tooth
A chronic infection around a baby tooth can damage the permanent tooth developing beneath it in the bone. The infection destroys the bone around the roots of the baby tooth and can reach the developing permanent tooth. On an X-ray, the damaged bone looks like a darker area. When a baby tooth is infected, its roots dissolve faster, so the tooth may start to wobble earlier than it should.
Changes in the permanent tooth usually only become visible once it comes through, sometimes several years later. This may be a white, cream or brown patch on the enamel of a single tooth, or a rotated tooth that comes through crooked. In extreme cases, the permanent tooth stops developing or a cyst forms around it.
It is not known exactly how often this happens. Studies give very different figures: from roughly one tooth in ten to more than half of the permanent teeth growing beneath an infected baby tooth. Much of the evidence suggests that the risk grows the longer the infection lasts.
Much of the evidence also suggests that what damages the permanent tooth is mainly the infection itself. When both options are possible, studies do not allow us to say whether it is better for the developing permanent tooth to give the baby tooth root canal treatment or to remove it. So the dentist chooses the approach for the particular tooth, and once the permanent tooth has come through, checks its enamel and position.
What happens when the dentist examines your child
A child with an abscess on a baby tooth is best seen by a dentist who works in paediatric dentistry every day. The dentist asks when the bump first appeared, whether the tooth has hurt, whether there has been a fever and whether your child has had a knock. They also ask about long-term illnesses and medicines. Then they look at the gum and the tooth, check for a sinus tract and swelling, and see whether the tooth is loose.
After the examination, the dentist takes an X-ray if the result could change the decision. With an abscess, this is usually the case. A small X-ray of one or a few teeth shows whether the infection has reached the bone between the roots or at their tips, how much of the roots is left and where the developing permanent tooth lies. The radiation dose from a dental X-ray is very small.
The dentist also looks for decay in the other teeth. In children, permanent teeth with deep grooves - for example six-year molars - can be protected with fissure sealants.
What to do first when pus appears by a baby tooth
If there is a pus-filled bump but no swelling and no fever, show it to a dentist within a few days, even if nothing hurts your child. If the gum is swollen, have your child seen by a dentist within 24 hours. With facial swelling, a fever, weakness or refusal to drink, get help the same day. Treating the tooth or removing it usually ends the infection that could harm the permanent tooth growing beneath the baby tooth.
Frequently asked questions
Can an antibiotic cure a baby tooth abscess in a child?
No. An antibiotic does not remove the bacteria from the tooth's canals, so once it is stopped, the infection usually comes back. With an abscess or a sinus tract without facial swelling and without a fever, it is usually not needed, because there are no studies showing that it helps children in this situation. It is prescribed when the infection is spreading beyond the tooth, and never instead of treating the tooth.
Can a baby tooth with an abscess be taken out straight away?
Yes, it can usually be taken out straight away, even while the infection is active. Removing the tooth lets the pus drain and removes the source of the infection, so it is often done at the first visit, with a local anaesthetic. When the infection is spreading to the face, the dentist sometimes gives an antibiotic first or refers the child to hospital. The order depends on the child's general condition.
Can the abscess come back after root canal treatment of a baby tooth?
Yes, although the treatment often succeeds. Bone heals slowly, so a problem may show up after months or even several years. That is why the dentist takes regular check-up X-rays until the tooth is replaced by the permanent one. If the sinus tract comes back or the darker area on the X-ray does not get smaller, the tooth is usually removed.
What is healing like in the first few days after a baby tooth is treated or removed?
After root canal treatment, the tooth may ache for anywhere from a few hours to a few days. After the tooth is removed, your child bites on a piece of gauze for 30–60 minutes. Until the anaesthetic wears off, do not give your child anything to eat, and make sure they do not bite their numb lip or cheek. Show the dentist a bump that persists or keeps coming back. If there is increasing pain, swelling or a fever, call the practice the same day.
What happens to the gap left by a removed baby tooth over the following months?
The neighbouring teeth may drift into the gap and take up the space the permanent tooth needs. Much of the evidence suggests that this happens fastest in the first months after the tooth is removed. The dentist assesses whether a space maintainer is needed, which is a small appliance that holds the space open. This depends on which tooth was removed and how long it will be until the permanent tooth comes through.
Read more:
- Paediatric dentist in Warsaw Wola
- Tooth abscess — does a tooth with an abscess always have to be removed?
- Paediatric dentistry: How to prepare your child for their first dental visit — a guide for parents
- Fissure Sealants in Children — When, How Often, and Whether They Really Protect Against Caries
- Comprehensive dental review: What does it contain and why is it crucial for health?
Content and liability disclaimer
This article is informational and educational in nature and does not constitute medical advice, a diagnosis or a therapeutic recommendation — it does not replace a consultation with a specialist. If you are experiencing symptoms, have doubts or are facing a decision about treatment, consult a dentist. The methods described and the data cited are general in nature. The results of scientific studies relate to populations, not to an individual patient. The course and outcome of therapy depend on the individual clinical situation and may vary between patients. No information contained in this article constitutes a guarantee of result. The content has been prepared with due care, based on publicly available medical knowledge and the scientific publications indicated in the Sources section. We do not advise taking or refraining from any health-related action solely on the basis of the content of this article, without prior consultation with a doctor.
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