Avulsed immature maxillary central incisor with 100 minutes of dry storage
A nine-year-old girl is brought to the clinic 100 minutes after falling from her bicycle and knocking out her upper right central incisor. The tooth was picked up from the road, wrapped in a paper tissue and has been dry since. She is otherwise healthy and takes no medication; her immunisations are otherwise up to date, though her mother is unsure about tetanus. On examination 11 is complete, has an open apex of about 1.5 mm and a small palatal enamel fracture; the socket walls are intact and there is no obvious alveolar fracture. The adjacent 21 is intruded by roughly 3 mm and grade I mobile, with no tenderness to percussion. Both lips have abrasions. Radiographs show no root fracture of 11, an open apex on 21 and no other displaced teeth. The girl is crying and will not open her mouth for a full examination; the mother wants the tooth put back and asks whether it will 'take'.
1. What factors determine the prognosis of 11, and what would you do with the tooth at this visit?
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The prognostic factors, in order of importance
- Extraoral dry time (worst feature here): 100 minutes. Periodontal ligament cell viability falls steeply after about 20 minutes dry and is effectively lost by 60 minutes. Replacement resorption and ankylosis are therefore likely.
- Storage medium: a paper tissue is worse than nothing - it is dry and wicks residual moisture. Milk, saline, saliva or the buccal sulcus would all have been better.
- Apex status: open, which is favourable for revascularisation and for a less catastrophic resorption pattern, and also makes the root easier to reposition.
- Socket and alveolar condition: intact here, which favours replantation.
- Handling: avoid touching the root surface; hold the crown only.
What I do at this visit Replantation is still generally indicated after 60 minutes of dry time, but with a very guarded prognosis and consent reflecting that. I would:
- Gently irrigate the socket with saline, inspect for debris, and replant with light digital pressure; if the socket has collapsed, I would not force the tooth.
- Suture any soft tissue, place a flexible splint for two weeks, check occlusion, and verify position radiographically.
- Prescribe systemic antibiotics, discuss tetanus status and refer for a booster if required, and advise chlorhexidine rather than brushing over the site.
- Explain to the mother that the likely outcome is ankylosis with failure of the root to grow with the alveolus, that decoronation may be the best option later to preserve bone, and that the alternative of leaving the tooth out and preserving the space is defensible if she prefers.
2. How would you manage the intruded 21, and what review schedule and instructions would you give?
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The 21 An intruded permanent incisor with an open apex and 3 mm of intrusion has a good chance of spontaneous re-eruption, because the developing root and open apex allow continued eruption. The first decision is therefore to wait and observe, not to reposition immediately.
- Confirm on a radiograph that the tooth is intruded and not displaced laterally, and exclude a root fracture.
- Splint only if there is associated mobility or alveolar fracture; here grade I mobility alone does not require it.
- Review at 2, 4 and 8 weeks with clinical photographs and radiographs. If there is no movement by about 8 weeks, orthodontic extrusion (or surgical repositioning if the tooth is very severely intruded) is the next step. Extrusion carries a risk of pulpal necrosis and external root resorption, so the pulp is monitored throughout.
The 11 Because the pulp is almost certainly necrotic with an open apex and a long dry time, I would plan pulp extirpation and either revascularisation-type treatment or calcium hydroxide medication, with a definitive decision at the two-week splint removal.
Reviews and instructions
- 1 week: soft diet, no biting on the splinted tooth, chlorhexidine rinse, analgesia, warning signs (swelling, sinus, mobility, discolouration).
- 2 weeks: splint removal, radiograph.
- 4 weeks, 3 months, 6 months, 12 months, then annually until growth is complete, looking for inflammatory resorption, replacement resorption, ankylosis and infraocclusion.
- Written advice to the mother, and a note to the family dentist.
3. The mother asks whether her daughter can simply have an implant later. How do you answer, and how do you record and escalate the case?
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The answer to the mother Not until growth is complete - typically the late teens for a girl - because an implant behaves like an ankylosed tooth: it does not move with the growing alveolus, so it becomes infraoccluded and can be left behind as the neighbouring teeth and bone develop. Before then, the options are a removable partial denture or a bonded resin-retained bridge from 12 to 21, which must be planned so it does not interfere with eruption or gingival health. The long-term plan also depends on what happens to the alveolar bone after the replanted 11 ankyloses; decoronation at the right time preserves ridge height and makes later implant placement simpler. She should be told in plain terms that the replanted tooth is being kept as a temporary measure and a space maintainer, not as a permanent solution.
Recording and escalation
- Full trauma notes: mechanism, time of injury, extraoral time, storage medium, who handled the tooth, tooth numbers, mobility, sensibility tests, radiographs, and the parent's decisions.
- Written information, safety-netting advice, and copies to the general dental practitioner.
- Tetanus status checked and referral made if not current.
- Safeguarding judgement: a bicycle fall with lip abrasions is plausible, but I would record the account in the child's own words, note who was present, and follow local child-protection procedures if the history and injuries were inconsistent or delayed presentation were unexplained.
- Behaviour management and a follow-up appointment when the child is calmer, since a full examination was not possible today.