Avulsion of an immature maxillary central incisor with 20 minutes of dry time
A 9-year-old boy is brought to the emergency clinic 50 minutes after falling from his bicycle. His upper right central incisor (tooth 11) was completely avulsed. His mother picked the tooth up by the crown, rinsed it briefly under tap water, and wrapped it in a dry paper tissue for about 20 minutes before placing it in a glass of semi-skimmed milk; estimated extraoral dry time is 20–25 minutes and total extraoral time about 40 minutes. The tooth has an open apex roughly 1.5 mm wide and no fracture. Clinically there is a blood clot in the socket, the alveolar bone is intact, tooth 21 is mobile grade I and tender to percussion, and tooth 12 has an uncomplicated enamel-dentine fracture. The boy is healthy, fully immunised, takes no medication and has no known allergies. His mother asks whether the tooth is worth replanting at all and whether it will 'take root' again.
1. Decide whether to replant tooth 11 and justify your decision using dry time, root maturity and expected prognosis.
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Yes, replant. Current International Association of Dental Traumatology guidance is to replant a permanent tooth with an extraoral dry time under 60 minutes, and this tooth's dry time of 20–25 minutes falls comfortably inside that window. The open apex is a further argument in favour: an immature root with a wide canal and thin dentinal walls offers a real chance of revascularisation, and even if revascularisation fails, the tooth retains bone and vertical height until the patient is old enough for a definitive replacement.
The honest prognosis must be given to the mother. Periodontal ligament cell survival falls steeply with dry storage, so I would expect a substantial risk of inflammatory root resorption or ankylosis, and the long-term survival of this tooth is uncertain - many replanted immature teeth are lost during adolescence. But the alternatives are worse: not replanting means immediate loss of alveolar bone in a 9-year-old and a much more difficult reconstruction later. Replantation is also time-critical, so the conversation should be brief and the consent documented after the tooth is back in the socket.
2. Outline your immediate technique, splint, medication and follow-up plan, including the endodontic strategy for an immature apex.
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Handle the tooth only by the crown. Rinse it with saline (not tap water, not scrubbing) and inspect the root surface; do not curette the socket or remove the clot - gently irrigate with saline and aspirate excess. Replant with light digital pressure, verify position clinically and radiographically, and suture any gingival laceration.
Splint with a flexible splint (0.3–0.4 mm orthodontic wire bonded to 12 and 21) for 2 weeks. Keep the tooth out of occlusion, soft diet for 2 weeks, 0.12% chlorhexidine rinse twice daily for 1 week, and systemic antibiotics - amoxicillin at paediatric dosage, with doxycycline as an accepted alternative in a child over 8 years. Confirm tetanus status. Analgesia with paracetamol or ibuprofen by weight.
Endodontically, do nothing now: the apex is open and revascularisation is the goal. Monitor vitality and periapical status; if pulp necrosis develops, the treatment of choice is a regenerative endodontic procedure (evoked bleeding, blood clot, bioceramic or MTA coronal plug) rather than conventional apexification. Follow-up at 2 weeks (splint removal), 4 weeks, 3 months, 6 months, 12 months and then yearly for 5 years, looking specifically for inflammatory resorption, ankylosis and obliteration.
3. How do you manage teeth 21 and 12, and what do you tell the parents about the long term?
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Tooth 21 has a concussion/subluxation injury: it is mobile and tender but not displaced. It needs no splint - flexible splinting is reserved for displaced or avulsed teeth - but it does need a soft diet for 2 weeks, meticulous oral hygiene, chlorhexidine, and monitoring. A pulp sensibility test at this visit is unreliable after trauma, so I would record it and repeat at 2 and 4 weeks; a negative response that persists with periapical changes signals necrosis, and in an immature tooth that again means a regenerative procedure rather than immediate apexification.
Tooth 12 has an uncomplicated crown fracture with no pulp involvement: seal the exposed dentine with a bonded restoration or, if the fragment is available, reattach it. No endodontic treatment is needed.
For the parents I would state clearly that the replanted tooth is a temporary solution with an uncertain lifespan, that root resorption may appear months later, and that attendance at every review is what protects the outcome. I would also give prevention advice - a custom mouthguard for cycling and sport - and explain that the 12 and 21 injuries need the same follow-up even though they look minor today.