What should I do if a tooth suddenly falls out?

Direct answer in 60 characters

If a permanent tooth is knocked out, hold the crown, not the root; put it back immediately and bite on gauze ⁵. If it cannot be put back, place it in milk and seek care promptly ⁶⁷. Do not put a primary tooth back (replantation may harm the developing permanent tooth underneath), but still take the child promptly for a dental examination ¹⁵. A tooth that loosens and falls out without trauma is not a replantation situation; seek dental care promptly ³.

For a missing tooth with respiratory symptoms, a prior loss of consciousness, or bleeding that will not stop, this site advises going directly to an emergency department or calling 119 ².

Scope: This guide is specific to Taiwan's healthcare system (National Health Insurance and Taiwan's Medical Care Act). The evidence for dental-trauma care and IADT guidance is internationally applicable; institutional matters such as tetanus-vaccination recommendations, National Health Insurance benefits, and channels for checking charges apply only to Taiwan.

A 30-second triage: what exactly fell out?

First identify what fell out. The actions for the four situations differ, and two are even the opposite of each other. The four pathways below are a communication framework compiled from the guidance in F3 through F20; they are not a diagnostic tool ².

• Situation 1: a permanent tooth completely knocked out by trauma (a fall, collision, or sports injury, with the root coming out too). The guideline calls permanent-tooth avulsion one of the few true emergencies in dentistry ⁴, and prognosis depends substantially on what is done at the accident site ³.
• Situation 2: a child’s primary tooth that has come out. The guideline expressly says a primary tooth should not be replanted ¹⁵.
• Situation 3: a tooth that loosened and fell out without trauma (more often in adults). This is not a replantation situation: the guideline lists severe caries or periodontal disease among individual situations in which replantation is not indicated ³.
• Situation 4: what fell out is not a natural tooth (hollow on the inside, porcelain or metal on the outside, and usually not shaped like a root). It is a crown, bridge, or removable denture that has come loose. Its management is unrelated to tooth avulsion; this article has no separate section for it. See the two related cards in the internal citation chain below ².

If no one at the scene can tell which it is, the guideline provides a route: instructions for on-site care may be given by telephone to people at the emergency site ⁴. In other words, calling a dental clinic or an emergency department for remote guidance is the route described in the guideline ²⁴.

Situation 1: a permanent tooth completely knocked out by trauma — follow these on-site steps

The guideline treats immediately putting the tooth back at the accident site as the priority action in this situation; storage media are used only when that cannot be done ⁴. The steps below correspond one by one to the on-site-care section of the second IADT 2020 guideline ⁵⁶⁷.

1. First make sure it is a permanent tooth. The on-site checklist begins by confirming this (primary teeth should not be replanted) ⁵¹⁵.
2. Keep the injured person calm ⁵.
3. Find the tooth; hold only the white crown and avoid touching the root, then try to put it back into the tooth socket immediately ⁵.
4. If the tooth is dirty, rinse it gently in milk, saline, or the patient’s own saliva, then return it to its original position ⁵. The guideline’s action here is “rinse it gently”; it does not include brushing, wiping, or soaking in antiseptic. This article does not add actions that the source does not state ²⁵.
5. After it is put back, bite on gauze, a handkerchief, or a napkin to hold it in place ⁵.
6. If it cannot be put back, place the tooth as soon as possible in a storage or transport medium immediately available at the scene. The guideline specifically says this needs to happen quickly because dehydration of the root surface begins within minutes ⁶. The preference order, from higher to lower, is milk, HBSS (Hanks' Balanced Salt Solution in the guideline; this article does not supply a separate Chinese name), saliva (for example, spit into a cup), and saline. Water is a poor medium, but it is still better than letting the tooth air-dry ⁶.
7. Bring the tooth with the patient to an emergency clinic or dental clinic ⁷.
8. See a dentist or dental professional immediately ⁷.

If it has already been put back at the scene, do not worry about whether it is perfectly positioned. The guideline says a dentist confirms the position clinically and by imaging; if it was put into the wrong socket or rotated, repositioning to the correct location may be considered within 48 hours after the injury ¹⁰.

How to count the time — this section is easy to get wrong

The guideline uses three strata based on “extra-oral dry time,” not “the time from leaving the mouth until the appointment.” They are set out below as in the original ⁸:

• Replanted immediately or within a very short time (about 15 minutes) at the scene: periodontal-ligament cells are most likely still viable ⁸.
• Kept in a storage medium (for example milk, HBSS, saliva, or saline), with a total extra-oral dry time of less than 60 minutes: the cells may be viable but compromised ⁸. (The guideline states this tier verbatim as "less than 60 minutes"; exactly 60 minutes is not covered by the guideline, and this article does not assign it to a tier. Whichever tier it falls in, the action is the same — get to a dentist promptly and have replantation assessed.)
• Total extra-oral dry time over 60 minutes: the cells are likely non-viable. The guideline expressly says this applies regardless of whether the tooth has been stored in a medium ⁸.

Before describing these strata, the guideline first says that minimizing dry time is critical to periodontal-ligament-cell survival; after 30 minutes of dry time, most periodontal-ligament cells are non-viable ⁸.

There is a crucial and easily misunderstood detail here: extra-oral dry time means the time the tooth is exposed to air and not in a storage medium. Putting the tooth into milk or saline stops the count of dry time; that is why a storage medium matters ⁸. The guideline lists the two conditions separately: one stratum is “kept in a storage medium and total extra-oral dry time under 60 minutes”; the other is dry time over 60 minutes, regardless of whether the tooth was subsequently put in a medium. The latter means that putting it in a medium after it has already been dry for over 60 minutes cannot undo that dry time; it does not mean that time in the medium itself counts as dry time ⁸. The guideline’s statement that most periodontal-ligament cells are non-viable after 30 minutes likewise refers to the dry state ⁸.

⚠️ Correction dated 2026-08-06: An earlier draft took the conservative reading that time in a medium also counted as dry time. A third-opinion review found that this conflicted with another passage in the same card (milk storage for up to 2 hours can retain more than eighty percent periodontal-ligament-cell viability). OP corrected the draft after a sentence-by-sentence ruling from the full IADT guideline. Practical implication: time after a tooth is already in milk does not move it into the “over 60 minutes” stratum.

What if you cannot tell whether it is a primary or permanent tooth? (for example around the age of 6, when teeth are changing) — do not force it back in. Put the tooth in milk or saline, take it with you, and seek care immediately so a dentist can determine it; a permanent tooth can be replanted by a clinician in the clinic, while a primary tooth is not replanted. This is this site’s conservative guidance based on the difference between those two management pathways (a structural compilation), not a guideline clause ³⁴.

In practice, remember to do two things at once, not choose between them: put the tooth back immediately, or put it into a medium immediately, and seek care promptly ⁶⁷. Putting it into a medium gives the cells a chance of survival, but it does not stop time: the guideline’s third stratum expressly says that after more than 60 minutes the cells are likely non-viable whether or not the tooth has been in a medium ⁸.

Are there clinical figures for context? A Brazilian five-year retrospective study assessed 62 replanted permanent teeth: after five years, 31 teeth (50.0%) remained in their sockets and 31 (50.0%) were lost because of external root resorption. Among the 25 teeth (40.3%) replanted within one hour, 16 (64.0%) remained and 9 (36.0%) were lost. Of all 31 lost teeth, 22 (71.0%) had an extra-alveolar time over one hour ²¹. The authors concluded that an extra-alveolar time of less than one hour was important for keeping a permanent tooth in its socket ²¹. This is a single-center retrospective study of 62 teeth, not an estimate of an individual prognosis; treatment and results vary by person and require a dentist’s assessment ²¹.

It has already been over one hour. Should I still bring the tooth in?

Yes. The guideline’s position is clear: delayed replantation has a poor long-term prognosis; the periodontal ligament becomes necrotic and is not expected to regenerate, and the expected outcome is ankylosis-related (replacement) root resorption ⁹. Yet even when extra-oral dry time exceeds 60 minutes, the decision to replant a permanent tooth is almost always still the correct one because replantation keeps future treatment options open ⁹. The guideline also notes that not replanting a tooth is an irreversible decision, so attempting to save it is appropriate ³.

Parents of a child also need to know that if a replanted tooth becomes ankylosed and infra-positioned, decoronation or procedures such as autotransplantation may later be needed; timing depends on the child’s growth rate ⁹. These are matters for shared decision-making between the dentist and parent. This article does not predict them.

How strong is the current evidence?

It is important to be candid: for the question of which interventions after replantation are better, the 2019 updated Cochrane systematic review identified 4 studies, 183 participants, and 257 teeth. It concluded that evidence is insufficient to support or refute the effectiveness of the different interventions, and all evidence was rated very low quality ²². Put differently, the on-site steps in the guideline have clear consensus, but comparative evidence for subsequent care remains weak ²². That is why this article makes no “success rate” promise.

Situation 2: a child’s primary tooth has come out

Management of a primary-tooth avulsion is the opposite of management of a permanent tooth; this is particularly easy to get wrong. The guideline expressly says that an avulsed primary tooth should not be replanted ¹⁵. It gives three reasons, one of them identified as the most important ¹⁵:

• Treatment creates a substantial burden for a young child (including replantation, splint placement and removal, and root-canal treatment) ¹⁵.
• It can cause further damage to the permanent tooth underneath or to its eruption ¹⁵.
• The most important reason is to avoid a medical emergency from aspiration of the tooth ¹⁵.

Not finding the tooth calls for more vigilance than finding it

The primary-tooth-avulsion table specifically says that the missing tooth’s location should be explored during the history and examination, especially if no adult witnessed the accident or there was a loss of consciousness ¹⁶. An avulsed tooth is most often lost outside the mouth, but it can be embedded in the soft tissue of the lip, cheek, or tongue; pushed into the nose; swallowed; or aspirated ¹⁶. If the tooth cannot be found, the guideline says the child should be referred to an emergency department for medical evaluation, especially if respiratory symptoms are present ¹⁶.

Care and follow-up after a primary tooth falls out

• Parent education: take care while eating to avoid injuring the traumatized soft tissue again. To encourage gingival healing and reduce plaque accumulation, parents may clean the affected area with a soft toothbrush or cotton swab and apply alcohol-free 0.1% to 0.2% chlorhexidine gluconate mouth rinse topically twice daily for one week ¹⁷. Whether and how this applies must still follow the treating dentist’s instructions.
• Follow-up: schedule a clinical examination after 6 to 8 weeks, and follow up again when the child is 6 years old to observe eruption of the permanent tooth ¹⁷.
• Why follow for so long: the guideline notes that primary-tooth trauma can affect the development and eruption of the permanent dentition; intrusion and avulsion injuries are more commonly associated with permanent-tooth anomalies ¹⁹.

Two background figures about dental trauma in children, and one reminder

The data cited in the guideline are that oral injuries among children aged 0 to 6 years account for 18% of all physical injuries, and the mouth is the second most commonly injured body area. A meta-analysis found a world prevalence of 22.7% for traumatic dental injuries affecting primary teeth ¹⁸. These injuries occur most commonly between 2 and 6 years of age ¹⁸.

One reminder: the guideline has a separate section on non-accidental injury. Clinicians should check whether the accident history is consistent with the injuries; when abuse is suspected, prompt referral for a full physical examination and investigation should be arranged ¹⁹. This is written for the clinical side, but it is useful for parents and childcare staff to know that it exists.

Situation 3: no trauma; the tooth loosened and fell out on its own (more common in adults)

The first point to know is that this is usually not a “put the tooth back” situation. In its general section, the guideline lists individual situations where replantation is not indicated, including severe caries or periodontal disease, an uncooperative patient, severe cognitive impairment requiring sedation, and serious medical conditions such as immunosuppression or severe cardiac conditions ³. The original wording matters: these are described as “individual situations” that must be dealt with individually ³. So this article says “usually not a replantation situation,” not “replantation is never possible.” This is an individual clinical judgment for a dentist.

As to reasons a tooth cannot be retained, caries and periodontal disease account for a large share in the literature. A systematic review reported proportions of extraction indications: caries 36.0% to 55.3% of all extractions, periodontitis 24.8% to 38.1%, trauma 0.8% to 4.4%, and periapical disease 7.3% to 19.1% ²⁵. Two qualifications matter: these are “indications for tooth extraction,” not “causes of a tooth falling out on its own”; and only 3 studies, totaling 4396 extractions, could be included ²⁵. Another common misreading should be avoided: the review’s statement that reliable estimates are lacking concerns extractions for non-dental and non-medical motives, not the proportions above ²⁵.

The third point, and this section’s key point, is this: if periodontitis is the cause, the lost tooth is treated as an indicator of overall severity, not as an isolated event. The 2018 periodontitis staging system explicitly includes tooth loss due to periodontitis in its severity basis, alongside periodontal breakdown and complexity of management ²⁶. Therefore, after a tooth falls out on its own, the useful next step is not merely filling that one gap but asking a dentist for a full-mouth assessment ²²⁶.

For what happens if it is not addressed, the literature can state an association with quality of life. A 2026 systematic review and meta-analysis (50 articles, 55 population-based cohorts, and 287 750 participants) found that people with nonfunctional dentition had about twice the odds of impaired oral-health-related quality of life compared with those with functional dentition (odds ratio 2.08; 95% confidence interval 1.72 to 2.52) ²⁷. This is population-level associative evidence and cannot be applied as an individual prediction ²⁷.

Whether and how to replace the tooth is covered in a separate card on this site (see the internal citation chain below); it is not repeated here.

Red flags: seek medical care immediately in these situations; the first three are emergency-department level

The red flags below are compiled from the guidance above and Taiwan official health education. They are a framework for communicating when seeking care and cannot replace clinical judgment ². For the first three (a missing tooth with respiratory symptoms, a prior loss of consciousness, or bleeding that will not stop), this site advises going directly to an emergency department or calling 119. The remaining four are information to volunteer when seeking care and do not necessarily require an emergency department ².

• The tooth is missing and there is coughing, wheezing, troubled breathing, inability to speak, or chest pain: the guideline says an avulsed tooth can be swallowed or aspirated, and if it cannot be found the child should be referred to an emergency department for medical evaluation, especially with respiratory symptoms ¹⁶. A necessary qualification: this original passage is in the primary-dentition (children) section, and this article did not find a guideline clause at the same level for adults. If an adult has a missing tooth and respiratory symptoms, this site likewise advises immediate medical evaluation; that latter sentence is this site’s conservative recommendation, not the guideline’s original wording ²¹⁶.
• No adult witnessed the accident, or the person lost consciousness: the guideline lists both as conditions in which the tooth’s location should be investigated more carefully ¹⁶.
• Bleeding does not stop: a systematic review of local haemostatic measures after dental treatment includes measures such as gauze pressure ²⁸. If you take antithrombotic medication, let healthcare professionals manage the situation. The same review says that stopping antithrombotics on one’s own because of fear of bleeding, or after bleeding, increases the risk of thromboembolic events ²⁸. Do not stop or increase medication on your own. The review’s original setting was bleeding after tooth removal; this article cites only the risk of stopping medication without direction and does not provide instructions for traumatic bleeding ²⁸.
• The wound may be contaminated: Taiwan’s Centers for Disease Control tetanus information says that a wound contaminated by soil, dust, animal or human feces, or caused by a rusty implement requires appropriate hospital treatment, and the patient should tell the doctor that the wound was contaminated ³¹. A tooth that falls onto the ground, a sports field, or a road fits this situation.
• You are unsure whether tetanus vaccination is still current: the IADT approach is to refer the patient to a physician to assess whether a tetanus booster is needed, because it cannot be assumed that everyone has completed immunization and boosters ¹³. Taiwan CDC advises one reduced-dose tetanus, diphtheria, and pertussis booster every 10 years after the primary series ³¹. Whether a booster is needed is for a clinician to determine.
• The tooth has not come completely out but is clearly displaced or loose: this is a different trauma category, and IADT has another guideline specifically for crown fractures and luxation injuries ²⁰. The repositioning action in the guideline is to move the tooth back into its socket under local anesthesia ²⁰. That is a dentist’s procedure, not something to force back yourself.
• A child’s account of the injury does not match the injuries: this is a guideline warning sign for non-accidental injury and calls for referral for a full physical examination ¹⁹.

Risk factors: conditions associated with a poorer outcome

• Longer extra-oral dry time is associated with poorer periodontal-ligament-cell survival: after 30 minutes dry, most cells are non-viable; after more than 60 minutes, the cells are likely non-viable regardless of storage medium ⁸.
• Not placing the tooth in a storage medium immediately: dehydration of the root surface begins within minutes ⁶.
• Using water as the medium: the guideline rates water as a poor medium, although still better than dry storage ⁶. In-vitro storage-medium evidence also differs: a systematic review of 15 studies found that, for storage up to 2 hours, HBSS, DMEM, milk, 10% and 20% propolis, and Viaspan conserved more than eighty percent periodontal-ligament-cell viability ²³. The review described milk as convenient, inexpensive, and readily available in most situations while able to keep periodontal-ligament cells alive ²³; however, these are pooled in-vitro human-cell-culture findings, not clinical effectiveness ²³.
• Pre-existing severe caries or periodontal disease: the guideline lists both among individual situations where replantation is not indicated ³.
• Long-term changes after delayed replantation: periodontal-ligament necrosis and ankylosis-related (replacement) root resorption are expected; a child may later need decoronation or autotransplantation ⁹.
• Age range in children: primary-tooth trauma occurs most commonly from 2 to 6 years of age ¹⁸.

Checklist before seeking care (8 questions)

1. What time did the tooth come out? How long was it dry in the air? Was it placed in anything in the meantime, and if so, what? (This is key information used by the guideline to stratify prognosis ⁸.)
2. Is it a permanent or primary tooth? How old is the person?
3. Was there a blow to the head, loss of consciousness, or vomiting? Did an adult witness the accident ¹⁶?
4. Was the tooth found? If not, is there coughing, wheezing, troubled breathing, or inability to speak ¹⁶²?
5. When was the last tetanus vaccination? Was the wound exposed to soil, dust, or a rusty object ¹³³¹?
6. Is the person taking antithrombotics or other long-term medicines ²⁸?
7. If replantation is planned: how long will the splint stay in place, and how many follow-up visits are needed? Under Taiwan's Medical Care Act, a medical institution treating a patient must inform the patient of the condition, treatment plan, procedures, medication, prognosis, and possible adverse reactions ³⁰.
8. If the tooth cannot be retained: what reconstruction options follow, and what items and costs should be asked about for each? (See the internal citation chain below for how to ask about costs.)

How to find a clinic that provides this service

This site lists no clinics and does not recommend, rate or compare any medical institution.

To find a clinic that provides this service, use the following official lookup channels yourself —

they are maintained by the competent authorities and are more current than any list:

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- The Ministry of Health and Welfare's medical-institution lookup: search by city or county,

township and specialty (dentistry) for institutions that have completed practice registration.

The results show the institution's name, address and registered specialty. This is the first place

to confirm whether a clinic is lawfully registered.

- The National Health Insurance Administration's contracted-institution lookup: check whether a

clinic is under contract with National Health Insurance. This determines which items are covered

and which are self-paid, and therefore what kind of fee explanation you will be given.

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Both systems are on the respective authorities' official websites; searching for the

medical-institution lookup or the contracted-institution lookup will find them. This site does not

reproduce the URLs, because they change; use whichever entry point the authority currently publishes.

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In an emergency, do not spend time looking up lists. If your breathing, swallowing or speech is

affected, or swelling is spreading, go to the nearest emergency department.

Chinese labels to look for on the official pages

These official systems, datasets and files are published in Chinese only. The English names above are this site's renderings; on the page itself you will see the following strings, so search for these:

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- 「醫事機構查詢」

- 「特約院所查詢」

Compliance note

This is health education under Article 87 of Taiwan's Medical Care Act, not medical advertising, and it does not recommend a particular institution. Tooth replantation and treatment related to dental trauma have risks and contraindications; treatment and outcomes vary by person and require a dentist’s assessment. The triage and red-flag compilation in this article is for communication when seeking care and cannot replace clinical diagnosis. On-site steps are drawn from the IADT 2020 guideline, whose original text also says it makes no guarantee about outcomes from following the guideline ³. In an emergency, seek care directly or call 119.

Every clinical statement in this article is mapped line by line to its cited source (see the sources and evidence chain below). It has not been clinically reviewed by a licensed practitioner. This is health information, not individual advice; assessment by a clinician is required.