Avulsed immature central incisor with delayed milk storage
An 8-year-old boy is brought to the clinic 40 minutes after falling from a bicycle. His upper right central incisor (tooth 11) was avulsed; the mother placed it in milk after approximately 25 minutes of dry storage. On examination he is alert, with a 1 cm abrasion of the upper lip and a laceration of the chin; there is no loss of consciousness or vomiting. Tooth 11 is present in milk, root intact, with an open apex. Tooth 21 is mobile (grade I) and tender to percussion with a slightly displaced crown palatally; there is no alveolar fracture on palpation. He has no medical history, takes no medicines, and his tetanus status is unknown. The clinic has 0.12% chlorhexidine, saline, composite and wire, and 4% articaine. Radiographs show an immature 11 root with a wide canal and no root fracture, and an open apex on 21. He is due to start school in two weeks.
1. What is the prognosis for tooth 11, and would you replant it? Justify your answer using extraoral dry time, storage medium, and apex status.
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The prognosis is guarded but replantation is still indicated. The tooth has an open apex, which means revascularisation is possible if the pulp is not infected; this is the main reason to replant immature teeth aggressively. The dry time was about 25 minutes and the total extraoral time about 40 minutes, with the tooth in milk for the remainder. Milk is a suitable storage medium because it maintains cell viability, and a dry time under 60 minutes is within the window in which replantation is generally recommended. I would replant immediately. I would not scale or curette the root surface or the socket, because that would remove viable periodontal ligament cells. The tooth should be handled by the crown, rinsed gently with saline, and replanted with firm but gentle pressure. If the dry time had been over 60 minutes, replantation is controversial and the prognosis is poor; many units would still replant in a child but would discuss the likelihood of ankylosis and infraocclusion with the parents. If the socket were collapsed or there were an alveolar fracture, I would refer for repositioning under local anaesthesia.
2. Outline your immediate management of teeth 11 and 21, including splint type and duration, medications, and instructions.
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After confirming tetanus status and obtaining consent, I would infiltrate local anaesthetic (4% articaine) and irrigate the socket with saline. Replant 11 and check position clinically and radiographically. Reposition 21 gently. Apply a flexible splint: a 0.016-inch nickel-titanium wire or nylon line bonded to 11, 12, 21, and 22; the splint should allow physiological movement. For the avulsed tooth, splint for two weeks; for the subluxated 21, two weeks is also appropriate. If there is an alveolar fracture, extend to four weeks. Antibiotics: amoxicillin for seven days is appropriate; doxycycline is preferred in adults for avulsion but is generally avoided under 12 years because of staining, so amoxicillin is the practical choice here. Refer for tetanus prophylaxis if not up to date. Chlorhexidine 0.12% rinse twice daily for one week, soft diet, avoid biting on the splinted teeth, and paracetamol for pain. Warn about swelling, increased mobility, or discolouration.
3. What endodontic and follow-up plan would you use for tooth 11, and what findings would make you intervene early?
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Because the apex is open, I would not start root canal treatment at the time of replantation. The aim is to allow revascularisation. I would review at two weeks, four weeks, three months, six months, and one year, then annually until the root is mature. At each visit I would check mobility, percussion, gingival healing, discolouration, and radiographically look for a widening periodontal ligament, periapical radiolucency, inflammatory resorption, or canal calcification. Signs of revascularisation include a narrowing canal and continued root development. If pulp necrosis with apical periodontitis develops, I would consider revascularisation (regenerative endodontic) treatment or apexification with an MTA apical plug; if inflammatory resorption is present, I would start root canal treatment with a calcium hydroxide dressing promptly, because resorption can progress quickly. Ankylosis shows as loss of the periodontal ligament space and progressive infraocclusion; there is no effective treatment, and the tooth may eventually need extraction and prosthetic replacement after growth. Tooth 21 also needs sensibility testing and review for necrosis or root resorption.