Dental trauma part 1: acute management of luxation/displacement injuries

Clinical findings

Concussed teeth will be tender to touch, but there is no increase in mobility or change in position of the tooth and, therefore, no alterations to the occlusion, as seen in Figure 1 of the UL1.

Radiographic findings

A radiograph of a concussed tooth should show a healthy-looking tooth with no obvious widening or changes in the periodontal ligament, as seen in the UL1 in Figure 2.

Treatment of primary and secondary teeth

The treatment for concussion in both primary and secondary teeth is to reassure patients (and their parents/carers if a child) and advise a soft diet for two weeks. They should be encouraged to brush their teeth normally as soon as possible. Pulpal monitoring is advised for one year, after which follow-up is as per the scheduled review for that patient.^1,2,3

Clinical findings

A subluxated tooth is tender to touch and is mobile but there is no displacement of the tooth from its original position. As a result the patient is able to bite together without any premature contacts. A pathognomonic sign is bleeding from the gingival crevice due to cleavage and tearing of the periodontal ligament, as seen in the UL1 in Figure 3.⁴

Radiographic findings

A radiograph of a subluxation injury should show a healthy-looking tooth with no obvious widening of the periodontal ligament, as seen in the UR1 in Figure 4.⁴

Clinical findings

Clinically, an extruded tooth appears longer than the adjacent teeth (as seen in Figure 5 of the UL1); it is usually mobile and can get in the way of the patient biting together.

Radiographic findings

A radiograph of an extruded tooth will show varying degrees of widening of the periodontal ligament, dependent on the degree of extrusion, and could be seen as an increase in the width of the periodontal ligament space, as seen in Figure 6, where the UL1 has been mildly extruded, or in severe cases, when the whole apical socket outline is seen.^1,4,6

Treatment of secondary teeth

The treatment for an extrusion injury is digital repositioning of the extruded tooth under local anaesthetic. A forward and back watch-winding motion is useful to push past any immature clot that may have formed. To check that the tooth is fully seated, ask the patient to bite together and check that there are contacts between the posterior teeth. The tooth is then temporarily splinted with a temporary material such as Triad™ (Dentsply Prosthetics, Pennsylvania, USA: obtainable from Henry Schein) (see section on avulsed teeth) and a check radiograph taken to make sure that the tooth is fully repositioned. The check radiograph shown in Figure 7 shows reduction in the periodontal ligament space around the UL1.^1,4,6

Once the tooth is in the correct position, a flexible splint should be applied and, in this case, preformed 0.018” stainless steel orthodontic wire was used with composite resin, as seen in Figure 8.

The recommended time for splinting in extrusive luxation is two weeks (Table 2) and the patient is advised to return to normal toothbrushing as soon as possible. If there are extensive soft tissue injuries present, supplementing the oral hygiene with diluted chlorhexidine mouthwash for a few days can be useful.^1,4,6

The tooth should be monitored for pulpal health, at subsequent follow-up appointments and a follow-up period of 5 years is advised.^1,4,6

Treatment of primary teeth

Mild extrusion (<3 mm) of a primary tooth can either be repositioned, being mindful of the position of the erupting successor, or left to reposition itself over time. In the case of severe extrusions (>3 mm), repositioning or extraction of the extruded tooth can be carried out but the latter may be more appropriate, particularly if the successor is close to erupting.^1,4,6

Clinical findings

Figure 9 shows the lateral luxation of the UR1 which, due to the displaced position, results in the patient being unable to bite together. The occlusal view of the UR1 (Figure 10) shows the extent to which the crown of the UR1 has been displaced palatally. When this happens, the apex moves labially and, in the presence of a dento-alveolar fracture, can slip in front of the fractured alveolus. As a result, the tooth is locked into position and is firm, unlike in extrusion injuries. Mobility is therefore an important sign to distinguish between these two injuries.^1,4,6

Radiographic findings

Taking a good periapical radiograph of a palatally displaced tooth is difficult and the resultant image is dependent on the direction of displacement, the positioning of the radiograph and the positioning of the X-ray tube.^1,4,6 As a result, a combination of widening of periodontal ligament space in some areas and loss of periodontal ligament space in other areas will be seen around the displaced tooth, as seen in Figure 11.^1,4,6

Treatment of secondary teeth

The management of a lateral luxation injury is digital repositioning under local anaesthetic, anaesthetizing both the buccal and palatal (or lingual) tissues. Owing to the apex being locked in front of the fractured alveolus, the key to repositioning the tooth is to disengage the apex first before moving the crown labially.^1,4 This is achieved by applying pressure to the apical region high in the sulcus. If this is not carried out before applying pressure to move the crown, the tooth will not move.^1,4,6 Furthermore, orthodontic repositioning of a laterally luxated tooth with the apex wedged in front of the fractured alveolus is also likely to be unsuccessful, or cause considerable damage to the apex of the tooth.^1,4,6 A quick check to ascertain if a repositioned tooth is in the correct position is to get the patient to bite together, ensuring that there are contacts between the posterior teeth.^1,4,6

As with repositioned extrusive injuries, the repositioned tooth should be stabilized temporarily with resin on the incisal edges, and a check radiograph taken. If a periodontal ligament space is created uniformly around the tooth, and the occlusion is correct, the tooth should be splinted using a flexible splint for four weeks. Again, the authors use 0.018” stainless steel orthodontic wire with composite resin, as seen in Figure 12.

As with all repositioned and splinted teeth, patients are advised to restrict their diet to soft foods and to get back to normal toothbrushing as soon as possible. If there are extensive soft tissue injuries present, supplementing the oral hygiene with diluted chlorhexidine mouthwash for a few days can be useful.

At subsequent appointments, the tooth should be monitored for pulpal health and a follow-up period of 5 years is advised.^1,4,6

Treatment of primary teeth

In the case of a lateral luxation injury to a primary tooth with no occlusal interference, the tooth should be allowed to reposition spontaneously. If there is a mild occlusal interference, selective grinding of the primary tooth out of ‘traumatic occlusion’ can be performed. A primary tooth with more severe occlusal interference could be gently repositioned but caution should be exercised as repositioning may damage the developing secondary tooth and therefore, in severe cases, extraction should be considered.¹

Clinical findings

Clinically, the incisal edge of the intruded tooth is more apical compared to the adjacent teeth and the appearance can be that of a fractured tooth with a resultant 'short clinical crown', as seen in the UL2 in Figure 13. When the tooth is driven into the socket, there is often a disruption of the gingival margins. Intruded teeth are firm and locked into position and, if you were to tap the tooth (although there is little value in doing this), there would be a high, metallic/ankylotic sound.^1,4,7

Radiographic findings

Radiographs of an intruded tooth will show loss of periodontal ligament space around the root, as seen around the intruded UL2 in Figure 14. In cases of suspected intrusion, such as milder cases, compare the position of the cemento-enamel junction (CEJ) of the injured tooth with the adjacent tooth. If the CEJ of a traumatized tooth is more apical compared to the non-injured adjacent tooth, then intrusion is the likely diagnosis.^1,4,7 Assessing the position of the CEJ relative to the crestal bone of both the injured and non-injured teeth can also help with the diagnosis.^1,4,7

Treatment of secondary teeth

Mild intrusions in immature teeth (up to 3 mm) can be managed by monitoring for a few weeks for spontaneous eruption. If no improvement is seen in the tooth position compared to the adjacent tooth, then digital repositioning is recommended before ankylosis develops.^1,4,7

For mild intrusions in mature teeth with closed apices, digital repositioning is recommended under local anaesthesia.^1,4,7 This is often described as surgical repositioning but, since the procedure does not involve surgery, the authors prefer to use the term digital repositioning, to stress the importance of keeping any further trauma to the tooth to a minimum.^1,4,7

Severe intrusions in teeth with immature and mature root formation (>7 mm for immature root formation; 3–7 mm for mature root formation), digital repositioning should always be undertaken as the first line of treatment under local anaesthetic.^1,4,7

As alluded to above, digital repositioning should be carried with the aim of repositioning the tooth with as little additional trauma as possible.

The tooth should be dis-impacted using a flat plastic instrument positioned between the crown and the gum margin, taking care not to touch and therefore damage the cementum. Whilst attempting this, the crown should be cradled between the thumb and forefinger to avoid avulsion when the tooth is dis-impacted. Once in the correct position (determined by the occlusion or possibly from a pre-injury photo of the teeth from a ‘Selfie’), the tooth should be held in place with a temporary splint and, once the position is checked with a periapical radiograph, flexible splinting should be applied, as seen in Figure 15.² The splinting time for intruded teeth is four weeks.^1,4,7

If there are multiple intruded teeth, it is sensible to start on one side with the tooth closest to an untraumatized tooth. Once that has been repositioned and temporarily secured in place, as described previously, move on to the next tooth until all the teeth are back in the correct position.^1,4,7 In these circumstances, a ‘selfie’ or photograph of teeth before the accident can be invaluable to correct repositioning. A normal looking periodontal ligament space would not normally be evident immediately after repositioning.

Whilst orthodontic repositioning is a recognized and well-documented treatment strategy in the management of severely intruded teeth, this approach has been unsuccessful in several cases in the past, leading the authors to adopt digital repositioning as their treatment of choice.

Again, a soft diet for two weeks, normal toothbrushing as soon as possible, and diluted chlorhexidine mouthwash (if needed) should be advised.

The tooth should be monitored for pulpal healing and a follow-up period of 5 years is advised. The pulp is likely to become necrotic in a tooth with complete root formation and root canal treatment should be carried out if there are two signs or symptoms of necrosis (Figure 16).

Treatment of primary teeth

If the apex of the primary tooth is displaced towards or through the labial bone plate, the tooth should be left to resolve spontaneously. If the apex is displaced into the developing secondary tooth germ, then extraction of the primary tooth should be considered.

Clinical findings

When a tooth is avulsed, the nerves and blood vessels at the apex of the tooth are severed. The periodontal ligament is torn at the interface between the root and the alveolus and the whole root surface is exposed.^1,8,9

Radiographic findings

A radiographic examination will reveal an empty socket, as seen in the UL1 region in Figure 19 and there may be an associated dento-alveolar fracture seen as radiolucent horizontal lines. As mentioned above, it is common to see an apical third root fracture fragment retained in situ, as seen for the UR1 in Figure 18.^1,8,9

Treatment for avulsed teeth – immediate replantation of secondary teeth

The overall management of avulsed teeth depends on the stage of root development and the extra-oral dry time. Indeed, the prognosis is directly related to the extra-oral dry time and a quick reference guide is provided in Table 3.^1,8,9 For the best long-term outcome, the tooth should be picked up by the crown and re-inserted as soon as possible, ideally within 5 minutes after the injury. This obviously relies on having knowledgeable and competent personnel at hand, who understand the procedure of replanting an avulsed tooth.^1,8,9

Once the tooth has been repositioned, the patient should bite on a handkerchief and go straight to a dentist. The next step should involve verifying that the tooth is in the correct position and applying a flexible splint for 2 weeks.^1,8,9

For a tooth with a closed apex, root canal treatment should be initiated as soon as possible, ideally within 7–10 days. For a tooth with an open apex, the aim is to monitor for signs of revascularization of the pulp space. If this does not occur and, in the presence of two clear signs or symptoms of pulp necrosis, root canal treatment is indicated.^{1,8,9,10,11,12}

Treatment for avulsed teeth with <60 minutes extra-oral dry time in secondary teeth

If the tooth cannot be replanted at the scene of the injury, it should ideally be stored in HANKS balanced salt solution manufactured as Save-a-Tooth® (Phoenix-Lazerus, Inc, Portland, USA). Unfortunately, this is not readily available in the UK and has a relatively short shelf life. An easy-to-find and cheap alternative is milk, which has been reported to maintain the viability of the periodontal ligament cells for up to 6 hours.¹ The patient should see a dentist as a matter of urgency where the tooth should be rinsed with saline and replanted under local anaesthetic, temporarily held in position, as seen in Figure 20, and its position confirmed on a periapical radiograph (Figure 21). When complete repositioning has been achieved, the tooth should be splinted to the adjacent teeth using 0.018” stainless steel orthodontic wire as previously described (Figure 22).^{1,8,9,10,11,12}

For a tooth with a closed apex, root canal treatment should be carried out as soon as possible and ideally within 7–10 days (Figure 23). For a tooth with an open apex, aim for revascularization as described earlier.^{1,8,9,10,11,12}

Treatment for avulsed teeth with >60 minutes extra-oral dry time in secondary teeth

If the tooth had been out of the mouth for a prolonged period of time, root canal treatment can be carried out prior to placing the tooth back into position.^{1,8,9,10,11,12} If time does not permit this, then root canal treatment should be started as soon as possible, as described above. In teeth with a prolonged extra-oral dry time, two additional steps should be taken to remove the necrotic periodontal ligament cells before repositioning is attempted.^{1,8,9,10,11,12} The authors routinely use the following protocol to achieve this; soak the tooth in sodium hypochlorite solution (up to 5%) for five minutes followed by 2% sodium fluoride solution for 20 minutes.^{1,8,9,10,11,12}

The tooth should then be replanted and the position verified, both clinically by asking the patient to bite together, as well as radiographically as previously described and then flexibly splinted for up to 4 weeks.

Root canal treatment should be initiated prior to replantation, if there is time, or as soon as possible (within 7–10 days) for both mature and immature teeth.

Use of systemic antibiotics for avulsed teeth

Whilst the value of systemic administration of antibiotics after replantation is still questionable, guidelines suggest administration of 100 mg doxycycline twice a day for one week in children over 12 years of age and adults, to reduce the risk of root resorption.^{1,8,9,10,11,12} It should not be used in children under 12 years of age and pregnant women owing to the risk of discoloration of the developing secondary teeth. In such patients, penicillin V or amoxycillin at an appropriate dose for age and weight should be used. In patients with an allergy to penicillin, erythromycin is recommended.^{1,8,9,10,11,12}

Endodontic considerations

If root canal treatment is carried out very soon (ideally within a few days) of the avulsion injury, the canal system should be sterile, and therefore single visit root canal treatment is appropriate.^8,9,10,11,12 If, however, there was a risk of a large inflammatory response that would result in a higher chance of resorption, then an intermediate intra-canal dressing should be used.^8,9,10,11,12 An antibiotic corticosteroid paste to reduce such an inflammatory response can be used, such as Odontopaste™ (Figure 24) (Australian Dental Manufacturing, Queensland, Australia). Unlike Ledermix paste™, this contains clindamycin and therefore will not cause discoloration of the dentine.^8,9,10,11,12

Poor prognosis replantation

There is a growing body of thought that suggests that patients or their parents may feel let down if an attempt is not made to replant an avulsed tooth, even when the prognosis is considered very poor.^8,9,10,11,12 Indeed, Professor Kenny in Toronto suggests that, no matter how poor the prognosis might appear, every attempt should be made to replant the tooth, and he advocates extra-oral root canal treatment if at all possible.¹³ The aim of replanting teeth with a poor prognosis is to allow bony healing and retention of the tooth until a more predictable approach to tooth placement, ideally with an implant, can be undertaken.^{1,8,9,10,11,12,13,14} In the growing patient, the replanted tooth could be retained until the patient reaches adult levels of growth and then be planned for an implant.¹⁴

In growing individuals, careful and diligent monitoring is essential to diagnose infraocclusion as a result of ankylosis when radical management, such as decoronation, is indicated.¹⁴

Contra-indications to replantation

The following teeth should not be replanted:

General advice for all traumatic dental injuries

General advice for all traumatic dental injuries should include a soft diet for up to four weeks, to avoid biting with the front teeth, and establishing and maintaining good oral hygiene. Brushing/massaging the area with a toothbrush (with adjunctive rinsing with dilute chlorhexidine in the presence of extensive soft tissue injuries) is beneficial to prevent accumulation of plaque and debris that is likely to hinder soft tissue healing. Contact sports should be avoided for three months and the importance of follow-up should be stressed.^1,2,3

Patients must also be made aware of the possible and often inevitable sequelae after traumatic dental injuries and advised to watch for signs of swelling, colour change, increased mobility and pain.^1,2,3

Dental Trauma UK has prepared patient information leaflets for members to download for free to use in their clinics (www.dentaltrauma.co.uk).²