What to Do If Your Tooth Gets Knocked Out

A permanent tooth that gets knocked completely out of its socket can often be saved if you act within minutes. The single most important thing you can do is get the tooth back into the socket as quickly as possible, or keep it in a moist environment like cold milk while you rush to a dentist. Every minute the tooth sits exposed and dry, the living cells on its root surface die, and those cells are what determine whether your body accepts the tooth once it is put back. The science behind replantation is straightforward, but the practical steps are counterintuitive enough that most people freeze or do the wrong thing.

The First Five Minutes Matter Most

When a tooth is knocked out, two things are immediately at risk: the blood supply to the inner pulp (the nerve-containing tissue inside) and the thin layer of ligament cells coating the root surface. Those ligament cells are what allow the tooth to reattach to the bone. They start dying the moment they are exposed to air. Research on replanted teeth consistently shows that outcomes hinge on how short the time outside the mouth is and what storage medium is used in the interim.¹

Here is what to do, step by step:

Find the tooth: Pick it up by the crown (the white part you normally see). Never touch the root. The root surface is covered in delicate periodontal ligament cells, and handling it crushes or contaminates them.
Rinse gently if dirty: If the tooth fell on the ground, hold it under a gentle stream of clean water for no more than ten seconds. Do not scrub, soap, or use disinfectant. Do not wrap it in tissue or cloth.
Try to push it back in: If you can, gently slide the tooth back into the empty socket yourself, making sure it faces the right way. Bite down softly on a clean cloth to hold it in place. This is the single best thing you can do.
If you can’t replant it: Put the tooth in a small container of cold milk. Milk’s pH and osmolality are close enough to what the root cells need that it buys significant time. Saline works too. Your own saliva is the next best option: either hold the tooth between your cheek and gum or spit into a cup and drop the tooth in. Never let it dry out.
Get to a dentist immediately: Call ahead so the office can prepare. If it is after hours, go to an emergency room, but understand that most ERs are not equipped for replantation and will refer you to a dental specialist.

The “push it back in yourself” step is where most people hesitate. It sounds aggressive, and many worry about doing damage. But a tooth sitting in its own socket, even imperfectly positioned, is in a far better environment than a tooth sitting in a cup. The dentist can adjust the position later.

Why Milk and Why Not Water

Tap water is actually harmful to the root cells. It has the wrong concentration of dissolved salts compared to body fluids, so water rushes into the ligament cells by osmosis and causes them to burst. Milk, by contrast, has a compatible balance of salts and sugars. A large study of replanted teeth in children found that teeth stored in a physiologic medium like milk had significantly lower rates of root resorption than those stored dry or in non-physiologic media. Teeth kept in non-physiologic storage for more than 30 minutes had markedly worse outcomes than those transferred to milk within that window.²

A separate survival study reported that storing avulsed teeth in milk reduced the tooth loss rate by more than half compared to teeth kept dry.³ That is a dramatic difference from something as simple as dropping a tooth into the nearest carton in the fridge. If milk is not available, saline (contact lens solution works in a pinch) or saliva are acceptable. The key principle is: never let the root dry out, and never put it in tap water.

The 30-Minute Threshold

You will sometimes hear that a knocked-out tooth must be replanted within 30 minutes. That number is a useful guideline rather than a hard cutoff, but the data behind it is real. A retrospective study of nearly 200 replanted teeth found that teeth with an extra-alveolar time longer than 30 minutes had significantly higher rates of root resorption than teeth replanted sooner.² The relationship between time and outcome is not all-or-nothing. A tooth replanted at 45 minutes in good condition still has a chance, and a tooth replanted at 15 minutes that was stored dry may do worse than one replanted at 40 minutes that sat in milk the whole time. The storage medium and the time work together.

That said, the practical message is clear: speed matters enormously. If you are at a sports field, a playground, or anywhere else where a tooth gets knocked out, the clock starts immediately. Do not spend 20 minutes searching for the “right” container or debating whether to go to the ER. Get the tooth wet, get it back in if you can, and go.

What the Dentist Does After You Arrive

Once you reach a dentist or oral surgeon, the tooth (if not already replanted) is placed back into the socket under clean conditions. The area is typically splinted, meaning the replanted tooth is connected to its neighboring teeth with a thin wire and composite material to hold it still while it heals. A semi-rigid splint, which allows slight natural movement, is preferred over a rigid one. Research has shown that rigid splinting and long splinting periods are associated with complications like the root fusing directly to the bone, a process called ankylosis.⁴

The splint usually stays in place for about two weeks. During that time, the periodontal ligament attempts to reattach to the root. In one documented case, root canal treatment was started one week after replantation and the splint was removed two weeks later.⁵ Root canal treatment is almost always necessary for fully mature teeth because the pulp inside the tooth typically dies after being severed from its blood supply. Left untreated, that dead tissue becomes a breeding ground for infection and leads to inflammatory resorption of the root.

A Cochrane review looking at different treatments given at the time of replantation found that the evidence supporting any one particular intervention over another is very limited. The review pooled four studies involving a total of 257 teeth and rated all the evidence as very low quality, concluding that there is not enough data to firmly recommend or reject specific post-replantation treatments.⁶ That does not mean treatment is futile. It means the research comparing one protocol to another is thin, so dentists largely follow consensus guidelines rather than evidence from large trials.

Children’s Teeth Are a Special Case

If a baby tooth gets knocked out, do not try to replant it. Forcing a primary tooth back into a child’s jaw risks damaging the developing permanent tooth underneath. The guidance for baby teeth is to stop the bleeding with gentle pressure, save the tooth for the tooth fairy if the child is into that, and see a dentist to make sure no fragments are stuck in the gum.

Permanent teeth in children, however, are a different story. Kids between about 7 and 12 are in a particularly tricky window: their permanent front teeth have erupted but the roots may not be fully formed yet. These immature teeth behave differently after replantation. On one hand, an immature tooth with an open root tip has some capacity for the pulp to regain its blood supply, a process called revascularization, which can allow the tooth to continue developing. Case reports have documented successful revascularization in immature replanted teeth, with continued root growth and no signs of infection over a year of follow-up.⁷ On the other hand, immature teeth appear to have a higher overall loss rate. One study found immature teeth had roughly a 50% higher loss rate after replantation, and that each additional year of the child’s age at the time of trauma (up to age 16) reduced the loss rate by about 15%.³

The practical takeaway for parents: if your child’s permanent tooth is knocked out, follow the exact same steps as for an adult. Pick it up by the crown, keep it moist, and get to a dentist fast. The younger the child and the less developed the root, the more urgently the dentist needs to assess whether the tooth can revascularize on its own or whether root canal treatment is needed.

Long-Term Survival and Complications

Even under ideal conditions, a replanted tooth faces an uncertain future. The most common complication is root resorption, where the body gradually breaks down the root. This comes in two main forms. Inflammatory resorption happens when infection from a dead pulp triggers an immune response that eats away at the root, and it tends to cause tooth loss relatively quickly. Replacement resorption (ankylosis) is a slower process: the body treats the root as bone and gradually replaces it, which can take years before the tooth is finally lost.

One long-term study tracked 49 replanted teeth and found that about a third were eventually lost. Among those lost, most were lost to inflammatory resorption, which happened on average within about two years. Teeth lost to replacement resorption lasted considerably longer, an average of about six years before they finally had to be extracted. Among the surviving teeth, more than half showed some degree of replacement resorption, and only about 44% achieved what researchers call functional healing, where the ligament truly regenerates.⁸

A separate study of 196 replanted teeth in children found a slightly more optimistic picture, with survival rates around 79% for mature teeth and 70% for immature teeth. But those numbers include teeth with ongoing replacement resorption that may eventually be lost.² So “survival” at follow-up does not always mean permanent success. When the periodontal ligament is too damaged to heal, the bone slowly absorbs the root, and the tooth is eventually lost over a period of years.⁹

This sounds discouraging, but context matters. Even a replanted tooth that lasts five to ten years buys significant time, particularly for a growing child whose jaw has not finished developing. A dental implant placed too early in an adolescent jaw can end up mispositioned as growth continues, so a replanted tooth that serves as a natural placeholder for several years is genuinely valuable even if it is eventually lost.

When Replantation Fails and the Alternatives

If the tooth cannot be saved, the main long-term replacement options are a dental implant, a fixed bridge, or a removable prosthesis. For most adults, a dental implant is considered the gold standard. A systematic review of implants placed after traumatic tooth loss found survival rates of about 97% for the implant itself and 95% for the visible crown, after an average follow-up of three and a half years. Complications were relatively uncommon, though bone augmentation was needed in a substantial number of cases because the trauma that knocked the tooth out often damages the surrounding bone as well.¹⁰

For teenagers and young adults whose jaws are still growing, implants are typically delayed until growth is complete, often into the late teens or early twenties. In the meantime, a temporary removable appliance (sometimes called a “flipper”) or a bonded bridge can fill the gap. Your dentist will factor in age, bone health, and the condition of the neighboring teeth when recommending the best route.

Most People Do Not Know What to Do

One of the frustrating aspects of dental avulsion is that the right first-aid steps are simple, but almost nobody knows them. A study surveying physicians and nurses in hospital emergency departments found widespread confusion about how to handle and store a knocked-out tooth, despite the fact that these are the professionals most likely to encounter the injury outside of a dental office.¹¹ Another study, conducted in Pakistan, found that among nearly 400 respondents including doctors, teachers, and the general public, only about 10% suggested immediate replantation as the right first-aid step. Among non-dentists specifically, the number dropped below 5%.¹²

The knowledge gap extends to schools, sports clubs, and households. The most common mistakes are wrapping the tooth in tissue (which dries it out), scrubbing the root clean (which strips the ligament cells), putting it in water (which bursts those cells), or simply throwing it away because it seems obvious that a tooth that fell out is gone for good. Spreading awareness of the milk trick alone could save a meaningful number of teeth every year.

Prevention Through Mouthguards

Most avulsions happen during contact sports, falls, bicycle accidents, and playground collisions. The sports-related category is the most preventable. Custom-fabricated mouthguards, made from a dental impression of your teeth, offer substantially better protection than the inexpensive boil-and-bite or stock types available at sporting goods stores. A review of mouthguard effectiveness in rugby found that stock (off-the-shelf) mouthguards are considered inferior and their use is discouraged, while custom-fabricated mouthguards are recommended for players in more vulnerable positions.¹³ Common dental injuries in sports include tooth fractures, intrusion, extrusion, avulsion, and jaw joint dislocation.¹⁴

Custom mouthguards cost more upfront but are more comfortable, fit better, and interfere less with breathing and speaking, which means athletes actually wear them. A mouthguard sitting in a gym bag protects nothing. If you or your child plays a contact sport, basketball, soccer, martial arts, hockey, or any activity with meaningful collision risk, a custom-fitted guard from a dentist is worth the investment.

The Emotional Side of Losing a Front Tooth

Avulsed teeth are almost always front teeth, which makes the injury highly visible. The psychological impact, especially on children and teenagers, is real and measurable. Research on adolescents has found that dental disorders including traumatic tooth loss have a profound effect on self-esteem and psychosocial behavior.¹⁵ A case study tracking an adolescent through aesthetic reconstruction after a dental fracture found that the injury had a clear negative impact on social wellbeing, and that after oral rehabilitation, the patient showed improved quality of life and self-confidence.¹⁶

This dimension is worth acknowledging because it affects how urgently families pursue treatment and how much distress the injury causes in the meantime. A missing front tooth changes how a child speaks, eats, and smiles in public. Even a temporary prosthesis can make an enormous difference in a young person’s willingness to participate in social life while waiting for a definitive restoration. If your child loses a tooth and is visibly distressed, ask the dentist about interim cosmetic options right away rather than treating the gap as something to endure until the permanent fix is ready.

1
PubMed Central. Management of 3 Avulsed Permanent Teeth: Case Report of a 3-Year Follow-up
2
PubMed. A retrospective study of survival of 196 replanted permanent teeth in children
3
PubMed. Survival of Replanted Permanent Teeth after Traumatic Avulsion
4
PubMed Central. Dental splints: types and time of immobilization post tooth avulsion
5
PubMed Central. Replantation of an Avulsed Tooth: A Case Report
6
Cochrane Library. Interventions for treating traumatised permanent front teeth with avulsion injuries
7
PubMed Central. Dental Pulp Revascularization in a Replanted Avulsed Immature Maxillary Permanent Central Incisor
8
Scientific Reports. Survival and complication analyses of avulsed and replanted permanent teeth
9
Australian Dental Journal. Interventions for treating traumatized permanent front teeth: avulsed (knocked out) and replanted
10
PubMed Central. Implant treatment after traumatic tooth loss: A systematic review
11
PubMed Central. Knowledge and Awareness of First Aid of Avulsed Tooth among Physicians and Nurses of Hospital Emergency Department
12
PubMed. First-aid knowledge about tooth avulsion among dentists, doctors and lay people
13
PubMed. Mouthguards. Protection for the mouth in rugby union
14
PubMed Central. Common Dental Injury Management in Athletes
15
PubMed Central. Impact of Dental Disorders and its Influence on Self Esteem Levels among Adolescents
16
PubMed Central. Aesthetic-functional reconstruction of dental fracture and its impact on the psychosocial aspect