Pedodontics
Lec.11 Dr.Sara Medhat Al-DabbaghFifth stage
Displacement of primary and permanent anterior teeth
(luxation)
The displacement of anterior primary and permanent teeth presents a challenge in diagnosis and treatment for the dentist.
Intrusion and extrusion of teeth
Intrusion:
It is the most severe form of luxation injury because it causes severe damage to the periodontal ligament resulting in a greater incidence of external root resroption. The tooth may be completely or partially intruded in to the socket. Clinically crown appears shorter. The best approach is to wait and watch for the tooth to re-erupt on its own.
Primary teeth
Intrusion by forceful impaction of maxillary anterior primary teeth is a common occurrence in children during the first 3 years of life, why? Frequent falls and striking of the teeth on hard objects may force the teeth into the alveolar process to the extent that the entire clinical crown becomes buried in bone and soft tissue. Although there is a difference of opinion regarding treatment of injuries of this type, it is generally agreed that immediate attention should be given to soft tissue damage. Intruded primary teeth should be observed, with few exceptions, no attempt should be made to reposition them after the accident. Most injuries of this type occur at an age when it would be difficult to construct a splint or a retaining appliance to stabilize the repositioned teeth. Normally the developing permanent incisor tooth buds lie lingual to the roots of the primary central incisors. Therefore when an intrusive displacement occurs, the primary tooth usually remains labial to the developing permanent tooth. If the intruded primary tooth found to be in lingual or encroaching relationship to the developing permanent tooth, it should be removed. Such a relationship may be confirmed from a lateral radiograph of the anterior segment.
Primary anterior teeth intruded as a result of a blow may often re-erupt within 3 to 4 weeks after the injury. These teeth may even retain their vitality and later undergo normal resorption and be replaced on schedule by their permanent successors. During the first 6 months after the injury, however, the dentist often observes one or more reactions of the pulp and supporting tissues, the most common of which is pulpal necrosis. Even after re-eruption a necrotic pulp can be treated if the tooth is sound in the alveolus and no pathologic root resorption is evident.
Primary teeth that are displaced but not intruded should be repositioned by the dentist or parent as soon as possible after the accident, to prevent interference with occlusion. The prognosis for severely loosened primary teeth is poor. Frequently the teeth remain mobile and undergo rapid root resorption.
The immediate and future prognosis for the pulp is more favorable if root formation is still incomplete at the time of the accident. Teeth with complete root formation seemed to undergo resorption more frequently than those with incomplete root formation.
Permanent teeth
Intruded permanent teeth apparently have a poorer prognosis than similarly injured primary teeth. The tendency for the injury to be followed by rapid root resorption, pulpal necrosis, or ankylosis is greater.
The treatment:
For a permanent tooth with a closed root end
Intrude less than 3 mm, is to allow the tooth to erupt without intervention. If no movement is evident after 2 to 4 weeks, the tooth may be repositioned either orthodontically or surgically before ankylosis can take place.
If the tooth is intruded 7 mm or more, the tooth repositioned surgically and stabilized for 4 to 8 weeks by means of a flexible splint.
In most instances the pulp will become necrotic with intrusive injuries in tooth with complete root formation. Root canal treatment should be initiated, with calcium hydroxide as a temporary canal filling material, 2 to 3 weeks after stabilization.
For a permanent tooth with an open apex
To allow it to erupt spontaneously. If no movement is seen within a few weeks, orthodontic repositioning should begin.
If the tooth is intruded 7 mm or more, the tooth can be repositioned surgically and stabilized by means of a flexible splint. Endodontic therapy is often required, however, and the tooth should be monitored closely while a decision on endodontic therapy is pending.
It appears that spontaneous eruption results in the fewest complications in immature teeth, regardless of the degree of intrusion.
The frequency of pulpal necrosis in teeth with complete root development is higher than in those with incomplete root development. Teeth with uncomplicated crown fractures with luxation and crown fractured teeth with intrusion had a higher incidence of pulpal necrosis than any other types of concurrent luxation. A concurrent luxation injury and complete root development are important risk factors of pulpal necrosis with uncomplicated crown fractures.
It seems that both treatment approaches to the treatment of severely intruded permanent teeth (early repositioning or waiting for spontaneous re-eruption) have demonstrated reasonably successful results. However, the affected teeth seems to benefit by early calcium hydroxide endodontic therapy with either treatment approach. The decision to reposition mechanically or hope for spontaneous re-eruption of intruded permanent teeth remains a matter of clinical judgment that may be based on several conditions associated with the particular case.
Extrusion:
It is called peripheral displacement or partial avulsion. It is partial displacement of tooth out of its socket (it appear longer). The extrusive luxation of a permanent tooth usually results in pulpal necrosis. The immediate treatment involves the careful repositioning of the tooth and stabilization.
If mature repositioned teeth do not respond to pulp vitality tests within 2 to 3 weeks after being repositioned, endodontic treatment should be undertaken before there is evidence of root resorption, which often occurs after severe injuries of this type. The need for endodontic intervention is virtually certain in cases of significant extrusion (more than 2 mm) of mature teeth. With extruded immature teeth, the clinician should monitor the situation frequently and be prepare to intervene with endodontic therapy, as described later, if conditions warrants.
Lateral luxation: displacement of tooth in any direction other than axial.
Clinical features:Tooth is mobile and displaced.
Bleeding from gingival crevice.
Tooth is tender to percussion and masticatory forces.
Radiographical features:
Widening of PDL space on one side and crushing of lamina dura on other side.
Treatment:
Administer local anesthesia if forceful positioning is anticipated.
Reposition the tooth in normal position using digital pressure.
Splint the tooth for 2 weeks and if there is a marginal bone breakdown then splint for 6-8 weeks
Advise soft diet.
Follow up period of 1 year.
AVULSION AND REPLANTATION
Term used to describe complete displacement of tooth from its alveolus. It is also called as exarticulation. Maxillary teeth are most common involved.Clinical features:
Bleeding socket with missing tooth.
Radiographical features:
Empty socket.Associated bone fracture.
If the wound is recent then lamina dura is visible otherwise is obliterated.
Treatment:
ReplantationIf apical foramen is not closed endodontic therapy is delayed till first signs of apical closure are seen.
If apical foramen is closed endodontic therapy is done after 1-2 weeks depending on type of replantation.
Replantation is the technique in which a tooth, usually one in the anterior region, is reinserted into the alveolus after its loss or displacement by accidental means.
Replantation of permanent teeth continues to be practiced and recommended, however, because prolonged retention is also achieved in, many cases especially when replantation occurs soon after the accident.
Importance of replantation
The replanted tooth serves as a space maintainer and often guides adjacent teeth into their proper position in the arch, a function that is important during the transitional dentition period.The replantation procedure also has psychological value. It gives the unfortunate child and parents hope for success even though they are told of the possibility of eventual loss of the tooth, the early result often appears favorable and softens the emotional blow of the accident.
If a parent calls to report that a tooth has been avulsed, and it can be determined that the injury is without other oral, neurologic, or higher priority physical complications, the dentist may instruct the parent to do the following (primary teeth should not be replanted):
Keep the patient calm
Find the tooth and pick it up by the crown (the white part). Avoid touching the root.
If the tooth is dirty, wash it briefly (10 seconds) under cold running water and reposition it. Try to encourage the patient/parent to replant the tooth. Bite on handkerchief to hold the tooth in position.
If repositioning is not possible, place the tooth in a suitable storage medium.
Seek emergency dental treatment immediately, unless the patient was knocked unconscious. If the child was unconscious for a period of time, first seek emergency medical evaluation for a concussion.
Stabilization of replanted teeth
After replantation of a tooth that has been avulsed, a splint is required to stabilize it during at least the first week of healing. Acceptable splint should meet the following criteria:
It should be easy to fabricate directly in the mouth, without lengthy laboratory procedures.
It should be able to be placed passively without causing forces on the teeth.
It should not touch the gingival tissues, causing gingival irritation.
It should not interfere with normal occlusion.
It should be easily cleaned and allow proper oral hygiene.
It should not traumatize the teeth or gingiva during application.
It should allow an approach for endodontic therapy.
It should be easy to remove.