Knocked-Out Tooth at Practice: The 30-Minute Protocol

A knocked-out permanent tooth — the clinical term is avulsion — can be successfully reimplanted if you act within 30–60 minutes. Survival rate is approximately 85% if reimplanted within 5 minutes of the injury, dropping to around 50% at 30 minutes and 25% at 60 minutes. The first action you take in the first 2 minutes determines the outcome — picking up the tooth wrong, storing it wrong, or waiting to act means the difference between a tooth saved and a tooth lost.

The Evidence Behind the Protocol

The clinical protocol for avulsed tooth management is standardised by the International Association of Dental Traumatology (IADT), whose 2020 guidelines represent the most current and widely cited evidence base for dental traumatology. The IADT guidelines are referenced by dental schools, emergency medicine programs, and sports medicine organisations globally, and the survival rate data they compile from prospective and retrospective studies provides the clearest picture of how time and storage medium affect outcomes.

The core finding of this literature is consistent across studies: every additional minute the avulsed tooth spends outside the socket, especially if stored incorrectly, reduces the probability of successful long-term reimplantation. The periodontal ligament (PDL) — the thin layer of cells and connective fibres that attached the tooth root to the socket bone — is the critical tissue. PDL cells remain viable for approximately 30 minutes when kept moist in an appropriate medium. They begin to desiccate and die within 10–15 minutes if the root is allowed to dry. Once PDL cells are dead, the reimplanted tooth can integrate with the bone through ankylosis (direct bone-to-root contact without PDL), but long-term outcomes for ankylotic teeth are significantly worse — they do not move with orthodontic forces, they may gradually be resorbed by the surrounding bone, and they typically require eventual extraction and replacement with an implant.

This is why the protocol is not a general guideline about "seeing a dentist soon." It is a minute-by-minute emergency response where every decision in the first thirty minutes has direct, documented consequences for the tooth's survival.

The Emergency Protocol: Step-by-Step

1. Step 1 — Find the tooth immediately (0–30 seconds): The tooth should be visible on the court, field, or mat. Do not delay to assess other injuries before recovering the tooth — the clock on PDL viability begins at the moment of avulsion. Pick the tooth up by the crown — the white enamel portion at the top. Do not touch the root. Do not wipe, scrub, or dry the root surface. The microscopic PDL cells attached to the root look like nothing — they are invisible to the naked eye — but they are everything. Disturbing the root surface removes or kills the cells that make reimplantation work.
2. Step 2 — Attempt immediate reimplantation (30–60 seconds): If the socket is clearly visible, the athlete is alert and cooperative, and there is no other severe facial injury, this is the best possible outcome. Gently rinse the tooth with cold milk or sterile saline if available — or with the athlete's own saliva if no liquid is at hand. Do not use tap water. Position the tooth above the socket with the correct orientation (match it to the adjacent teeth — the smooth curved face goes outward), and gently but firmly press it back into the socket. It should seat with moderate resistance. If you feel significant resistance, stop — do not force it. Have the athlete bite down gently on a folded piece of gauze or clean cloth to hold the tooth in place while you arrange immediate transport to a dentist.
3. Step 3 — If immediate reimplantation is not possible, store the tooth correctly: If the athlete is unconscious, in shock, bleeding significantly from other facial injuries, very young and distressed, or the socket is unclear or occupied by blood clot, do not attempt on-site reimplantation. Instead, place the tooth immediately in cold milk (best readily available option), sterile saline, or have the alert, adult athlete hold it between the inner cheek and lower gum — gently biting on it, not clenching hard, and not swallowing. If a Save-A-Tooth kit (Hank's Balanced Salt Solution) is available in the facility first-aid kit, this is the optimal storage medium. Do not store the tooth in water under any circumstances. Do not wrap it in tissue or cloth. Do not put it in ice.
4. Step 4 — Contact a dentist immediately: Call the nearest dental practice or emergency dental line. Use the specific word "avulsion" — it is the clinical term that triggers emergency protocols at dental practices. Say: "We have a dental avulsion — a permanent tooth was knocked out approximately [X] minutes ago. We need emergency reimplantation." Most dental practices will see an avulsion case immediately, ahead of scheduled appointments. If you are uncertain which practice to call, your team's official medical support, a local hospital emergency dental service, or a hospital emergency department are all appropriate escalations.
5. Step 5 — Transport immediately: The athlete needs to be in a dental chair within 30 minutes of the avulsion for the best outcomes. This means transport begins now — not after the game, not after the athlete is calmed down, not after you finish the coaching session. Someone other than the athlete should drive. The athlete should hold the storage container or, if the tooth is in the mouth, should sit still and not move the jaw forcefully. Document the time of avulsion when transport begins — the dentist will need this information.

Why Milk? The Science of Storage Media

The choice of milk as the recommended emergency storage medium is not arbitrary — it reflects the specific biology of periodontal ligament cell survival. PDL cells are live cells with normal osmotic requirements, membrane integrity needs, and pH sensitivity. The storage medium needs to match these requirements closely enough to maintain cell viability for the transport window.

Tap water is the most common improper storage medium used in practice emergencies, and it is genuinely harmful. Tap water is hypotonic relative to PDL cells — its salt concentration is far lower than the cells require. When PDL cells are immersed in hypotonic water, osmotic pressure drives water into the cells, causing them to swell and lyse (burst). Studies have shown that PDL cell viability drops dramatically within 5–10 minutes in tap water, compared to 30–60 minutes in appropriate media. The difference between tap water and milk is not theoretical — it is the difference between cells that can support reimplantation and cells that cannot.

Whole milk has an osmolarity of approximately 280–290 mOsm/L, which is close to the osmolarity of PDL cells and the blood plasma that surrounds them. It also has a pH of approximately 6.5–6.8, within the viable range for PDL cell maintenance. Importantly, whole milk is present in essentially every sports facility — in coolers, at concession stands, in the kit room fridge. It is the right emergency medium because it is effective and it is there.

Hank's Balanced Salt Solution (HBSS), marketed as Save-A-Tooth, is purpose-formulated for exactly this application. Its osmolarity, pH, and ion concentration are matched to PDL cell physiology, and research studies demonstrate PDL cell viability maintenance for up to 24 hours when the tooth is stored correctly in HBSS. This is why sports medicine organisations recommend coaches carry it — but milk remains the right choice when HBSS is not available, which is most real-world practice emergencies.

Primary Teeth vs Permanent Teeth: A Critical Distinction

The entire protocol above applies exclusively to permanent (adult) teeth. If the avulsed tooth is a baby tooth — a primary tooth — the correct protocol is the reverse: do not reimplant.

Under each primary tooth in a child's jaw sits the developing bud of the corresponding permanent tooth. Reimplanting an avulsed primary tooth risks pushing it into contact with the developing permanent tooth bud, potentially causing damage to the permanent tooth's structure, eruption path, or developmental timing. The risks of reimplanting outweigh the benefits in primary teeth, and the IADT guidelines explicitly advise against it.

Instead, if a child's primary tooth is knocked out: keep the tooth for confirmation of age (a dentist can confirm primary versus permanent from the tooth morphology), keep the child calm, control any bleeding with gentle gauze pressure, and take the child to a dentist the same day for assessment. The dentist will evaluate whether the socket and adjacent permanent tooth bud are undamaged. No emergency urgency around the tooth itself, but same-day assessment is important for the surrounding structures.

Identifying primary versus permanent teeth in an emergency is easier than it sounds: primary teeth are notably smaller than permanent teeth, tend to have less distinct root anatomy visible at the fracture point, and in children under age 6–7 are almost certainly primary. If you are uncertain whether a tooth is primary or permanent, follow the protocol for permanent teeth until a dentist can confirm — the risk of incorrectly reimplanting a primary tooth is real, but the risk of not reimplanting a permanent tooth because of uncertainty is worse.

The Coach's Dental Emergency Kit

Standard first-aid kits at most sports facilities include bandages, antiseptic, and cold packs. Almost none include the specific items needed for a dental emergency. The IADT and sports dentistry organisations recommend every practice facility serving contact sport athletes maintain a dedicated dental emergency kit. The cost of the entire kit is under $25, and it can be assembled from a single online order.

1. Save-A-Tooth (Hank's Balanced Salt Solution): The purpose-formulated tooth storage medium. Available online, long shelf life, specifically designed for this application. This is the single most important item. It costs approximately $15–20 and is the difference between 30 minutes of viability and potentially 24 hours.
2. Sterile saline or cold whole milk: Secondary storage option if HBSS is unavailable. Saline can be kept in the kit; whole milk is typically available in facility kitchens. Either is significantly better than tap water.
3. Clean gauze (sterile pads, 4x4): For gentle bite pressure after reimplantation, for absorbing bleeding from the socket, and for wrapping a broken tooth fragment. Keep several pads in the kit.
4. A small clean container with a secure lid: For transporting the tooth if storage medium other than Save-A-Tooth is used. A clean, sealable specimen container or small Tupperware with the storage fluid inside. Save-A-Tooth comes with its own container.
5. Emergency dental contact card: The name and phone number of the nearest dentist who accepts dental emergencies, plus the nearest hospital with emergency dental services. Update this card seasonally. Post a copy in the facility first-aid room and keep one in the kit. The worst moment to search for an emergency dentist is while an athlete is in pain with an avulsed tooth in a milk container.

The total cost of this kit — Save-A-Tooth, gauze, container, and a laminated contact card — is roughly $20–25. The cost of replacing a single avulsed tooth that was lost due to improper handling is $10,000–$20,000 over a lifetime, including implant placement, crown, and maintenance. The return on investment for the kit is essentially infinite.

After Reimplantation: What Happens Next

Successful reimplantation at the emergency visit is the beginning of the dental management, not the end. The athlete will require specific follow-up care that they need to understand before leaving the dental surgery.

A flexible splint — a thin wire bonded to the reimplanted tooth and the adjacent teeth with dental composite — is typically placed to stabilise the tooth while the periodontal ligament re-establishes its attachment. IADT guidelines recommend a flexible splint for 1–2 weeks for most avulsion cases; rigid splinting has been shown to promote ankylosis and is no longer the standard. The splint limits chewing and makes oral hygiene more challenging — both are factors for athletes managing a training and competition schedule.

Root canal treatment (endodontic therapy) is typically scheduled within 7–14 days of reimplantation for teeth whose root apex is closed (fully developed roots). The pulp of the tooth — the nerve and blood vessel tissue inside the root — does not typically revascularise after avulsion, and retained pulp tissue can cause infection and root resorption. Root canal treatment removes the pulp and fills the root canal system to prevent this. Athletes who have been through a root canal often report that it is far less uncomfortable than expected — the tooth is numbed and the procedure is primarily preventative at this stage, not pain management.

Follow-up radiographs (x-rays) are scheduled at regular intervals — typically 4 weeks, 3 months, 6 months, and annually — to monitor for root resorption, ankylosis, and bone healing. The athlete should understand that successful reimplantation does not guarantee permanent retention: some reimplanted teeth undergo progressive root resorption over months to years, even with technically correct emergency management. Long-term survival statistics for properly managed avulsion cases are good but not perfect.

Sports With the Highest Avulsion Risk

Dental avulsion is not uniformly distributed across sports. The incident pattern reflects the forces involved, the protective equipment used, and the type of contact that characterises each sport. According to data published in the Journal of the American Dental Association (JADA) dental injury epidemiology literature, the sports with the highest avulsion risk are those combining high-velocity projectile or opponent contact with low mouthguard compliance.

Basketball consistently records some of the highest dental injury rates in non-mandated-protection sports, driven by incidental elbow and forearm contact during rebounding and defensive play combined with mouthguard compliance rates that studies place as low as 7–35% in recreational and amateur leagues. Rugby (union and league) has among the highest contact-sport dental injury rates in published literature but benefits from substantially better mouthguard compliance where mandatory use rules are enforced. Hockey (ice and field) presents avulsion risk from stick, puck, and player contact, with mandatory mouthguard rules at most organised levels providing some protection. Martial arts — karate, taekwondo, MMA — carry high avulsion risk from direct facial strikes; compliance varies enormously by organisation, with combat sports organisations typically requiring mouthguards and point-fighting formats often not. Baseball and softball present avulsion risk from ball and bat impact, primarily in sliding and fielding injuries; compliance is low at amateur levels. Cycling presents avulsion risk specifically in crash scenarios — not from ongoing contact but from the high-energy, face-first fall pattern of road cycling crashes at speed.

The full dental injury rates, by sport and injury type, are compiled in detail on the dental injury rates by sport reference page. Athletes in high-avulsion-risk sports should review the mouthguard guide — a properly fitted custom guard distributes impact across the dental arch and significantly reduces avulsion risk from direct facial contact.

Related reading: Best Mouthguard for Athletes · Dental Injury Rates by Sport · Return-to-Training After Extraction · Exercise After Wisdom Teeth Removal · Training After a Dental Implant · Ball Impact and Dental Trauma in Table Tennis

The Athlete's Mouth — an Edges & Nets guide. Last updated June 2026.

Frequently asked questions

Can a knocked-out tooth be saved?

Yes — a knocked-out permanent tooth can very often be saved if you act immediately and correctly. Published success rates from the International Association of Dental Traumatology (IADT) 2020 guidelines show approximately 85% long-term survival when reimplanted within 5 minutes. Even at 30–60 minutes, reimplantation is worth attempting. The key variables are: keeping the periodontal ligament cells on the root alive (storage medium and speed) and getting to a dentist or emergency facility immediately.

How long do you have to save a knocked-out tooth?

The critical window is 30 minutes for the best outcomes. Within 5 minutes of avulsion, reimplantation produces approximately 85% long-term success. At 15–30 minutes, success rates are substantially lower but still clinically meaningful — reimplantation is still worth attempting. Beyond 60 minutes with the tooth dry, the periodontal ligament cells have desiccated and the prognosis for long-term retention is poor. Storage in milk or Hank's Balanced Salt Solution (Save-A-Tooth) extends viable storage time to approximately 60 minutes — which is why carrying these media matters.

What is the best thing to store a knocked-out tooth in?

The best commercial option is Hank's Balanced Salt Solution (HBSS), marketed as Save-A-Tooth — it is specifically formulated to match the osmolarity of the periodontal ligament cells and maintains cell viability for up to 24 hours in research settings. In a real-world emergency without HBSS, cold whole milk is the best widely available alternative — its osmolarity is close to that of PDL cells, and it maintains viability for 30–60 minutes. Saline is a reasonable second choice. Tap water is the worst choice — its low osmolarity lyses PDL cells within minutes. Never store the tooth dry or wrapped in tissue.

Should you reimplant a knocked-out tooth yourself?

If the conditions are right — the athlete is alert and cooperative, the socket is clearly visible and undamaged, and you have clean hands or gloves — gentle self-reimplantation or coach-assisted reimplantation is the recommended protocol for permanent teeth. The IADT guidelines explicitly encourage immediate reimplantation before transport to a dentist, because the time saved by reimplanting on-site typically outweighs any risks from the reimplantation itself. Do not attempt reimplantation if the athlete is in shock, if the socket is unclear, or if there are other facial injuries that suggest jaw fracture.

What is a tooth preservation solution and should coaches carry it?

A tooth preservation solution is a fluid specifically designed to maintain the viability of the periodontal ligament cells on the root of an avulsed tooth. The most widely available product is Save-A-Tooth, which contains Hank's Balanced Salt Solution (HBSS) — a sterile, pH-buffered saline that matches the osmolarity of living PDL cells. It is available online for approximately $15–20, has a long shelf life, and fits in a small kit bag. The American Academy of Pediatric Dentistry and the IADT both recommend coaches and athletic trainers carry it. Coaches who oversee contact sports should treat it as essential first-aid equipment alongside an AED and wound kit.