Trauma to an immature incisor

TRAUMA TO AN IMMATUREINCISOR

By Dr.Hyder Mohammed

Case presentation

SUMMARY

An 8-year-old girl has fractured her upper right permanentcentral incisor tooth.

HistoryComplaintThe child is brought in as an emergency by her mother, complaining of a broken front tooth.

History of complaintTwo hours prior to presentation the child had slipped at school, hitting her mouth. One front tooth appears to be broken.

Medical historyThe child is healthy.

Dental historyThe child has attended the dentist irregularly, has no caries and no experience of operative dentistry. Her mother states that the broken tooth had not appeared normal and may have been decayed.

Did the patient lose consciousness? admitted for 24 hours of observation. in this case the patient did not lose consciousness.

Was a piece of the tooth broken off and was it found?this case no fragment was found.

Has the patient suffered trauma previously? Previous trauma to this tooth could have resulted in arrested root development, disturbed crown formation or pathological mobility prior to this incident, depending on the age and stage of dental development at the time. Such changes could affect treatment and might explain the parent’s observation that the tooth was not normal. In this case no previous trauma could be recalled by the parent.

Was the damaged tooth fully erupted before the accident? In early mixed dentition, incisors on opposite sides of the mouth may be at different stages of eruption. At this age it would be expected that eruption would be complete but there is wide variation in eruption date and rate. It would be possible to misinterpret incomplete eruption as an intrusion injury if the original degree of eruption were not known. In this case, the child’s mother reported that both front teeth were fully erupted.

What object or surface did the child hit with her mouth? Injury on surfaces such as playgrounds, roads and pavements carries the risk of contaminating the wound with dirty particulate material. Sometimes such foreign material even enters intraoral wounds. Thorough debridement would then be required. It would also be necessary to check the child’s immunization status for tetanus prophylaxis and arrange a booster dose if required. In this case, the child hit the edge of a table.

ExaminationExtra-oral examination

The child is distressed but is readily examined. There is some slight swelling of the upper lip but no external abrasions or lacerations.

Intraoral examinationThe appearances of the teeth , What do you see?

erythematous and swollen

less than 1 mm of the tooth is visible

The visible fragment appears to be an intact incisal edge

What additional examination(s) would you perform?

injury to the adjacent incisors and teeth in the lower labial segment should be investigated.

• Vitality, • mobility, • tenderness to percussion

• a periodontal probe should be gently inserted into the labial gingival sulcus to confirm or exclude the presence of a deep pseudo-pocket which would indicate traumatic displacement.

Child abuse

What is your initial differential diagnosis?

There are two main possibilities

• The central incisor has been almost completely intruded (intrusive luxation)

• Crown has been fractured horizontally at gingival level.

InvestigationsRadiographs are required to visualize the intruded/ fractured tooth and to assess damage to it and the adjacent teeth. Periapical views should be taken of all upper incisors to detect possible root fracture and to assess the stage of root development of the incisors. In intrusion injuries the force of the blow is directed upwards so that it is unlikely that the lower incisors have been damaged. What does the radiograph show?The radiograph shows a severe intrusive luxation of the maxillary right permanent incisor. The periodontal ligament space is indistinct or obliterated in part. There is no crown or root fracture visible, and the root is immature with a wide open apex.

Tests of vitality of all incisors are required.

if the patient is sufficiently composed to allow it, all the incisors should be checked for vitality, preferably by electric pulp testing. Teeth recently subjected to trauma may not respond to testing (‘concussion’) and testing teeth with open apices may give an artificially low reading. However, it is important to take a baseline reading soon after the injury so that if vitality does not recover, treatment may be instituted without delay.

What is your final diagnosis?The patient has an intrusive luxation to the permanent central incisor. This tooth also has several discrete hypoplastic enamel

defects that were present before the accident.

What types of tissue injury result from intrusion and what are their complications?

Will the tooth re-erupt or should it be surgically repositioned?

all mature teeth (closed apex) and over 60% of immature teeth become nonvital as a result of intrusive luxation. Therefore, it is advisable to reposition the tooth as rapidly as possible so that access to the pulp chamber can be facilitated before pulp necrosis occurs. intruded teeth with open apices do have the potential for re-eruption, but if this has not commenced within 1 week, intervention is required. There is at present no evidence to indicate the optimal treatment for the intrusive luxation of permanent teeth. Given sufficient cooperation, immediate surgical repositioning of the tooth will immediately restore the appearance. This should be followed by a short period of splinting of 7–10 days. This option may, however, increase the likelihood of external root resorption and loss of marginal bone support. relatively rapid orthodontic extrusion over a period of 3–4 weeks is considered less traumatic and less likely to induce resorption.

In this case, spontaneous eruption was awaited, but was very slow. Electric pulp testing indicated early pulp necro- sis. The tooth was then extruded rapidly with a simple orthodontic appliance engaged on to a bracket attached to the labial surface of the intruded tooth. As soon as there was adequate access to the pulp chamber, the necrotic pulp was extirpated, the canal cleaned and obturated with non- setting calcium hydroxide paste.

What immediate treatment is indicated?immediate treatment aims to prevent subsequent external root resorption, preserve marginal bone support and prevent sepsis. Teeth with a closed apex should be treated by immediate pulp extirpation and placement of a non-setting calcium hydroxide root canal dressing. immature teeth should be monitored for spontaneous re-eruption and loss of vitality. a 5-day course of systemic antibiotics should be prescribed, and the false gingival pocket surrounding the intruded crown gently irrigated with chlorhexidine.

How would your management have differed if the patient had been a 3-year-old child with an intruded primary incisor?Mild intrusive luxation injuries in the primary dentition may be treated with reassurance and observation though parents should always be warned that damage to the permanent successor is common. Partial or sometimes total re-eruption over the following months is usual.

However, extraction should be performed without delay if a combination of periapical and lateral radiographs demonstrate that the deciduous tooth has impinged on the follicle of the underlying tooth or if there is subsequent loss of vitality. as in the permanent dentition, vitality must be monitored carefully if the apex is closed at the time of injury. Pulp tests in young children are often unreliable because of lack of understanding, and a close watch must be kept for colour change.