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 Abstract
Traumatic dental injuries can cause serious aesthetic,
functional, and psychological
consequences. Time is one of the most
critical factors determining clinical
outcome; all dental injuries should be
considered as true emergencies. Luxated
and avulsed teeth should be considered
for immediate action in order to
maximize the chance for long-term
retention. Other injuries can be
complicated if not treated shortly after
the traumatic event. It is the
responsibility of the emergency
physician to direct patients to
appropriate dental consultants in a
timely fashion. Although dental
interventions will usually follow
management of life-threatening injuries,
dental consultation in this situation
should be sought as soon as possible
especially in younger patients. This
review will emphasize the emergency
management of luxation dental trauma and
its endodontic consideration for
permanent dentition.
Introduction
In some communities, acute dental trauma has been shown to affect almost
one-half of the population (1). A large
US study indicated that 25% of the
population 6 to 50 years of age may have
sustained traumatic injuries to the
anterior teeth(2). An Australian study
by Stockwell in 1988 determined that the
incidence of trauma to the anterior
permanent teeth in 6-12 year old school
children was 1.7/100 children/year while
involving 2.1 teeth/100 children/year
(3). An English study by Hamilton et al.
(1997) determined the incidence of
trauma to permanent incisors and related
soft tissues as four cases/100
children/15 months, which was almost
twice the incidence of the Australian
study(4). The outcome of traumatic
events involving teeth depends on three
factors: the extent of injury, the
quality and timeliness of initial care,
and the follow-up evaluation and care.
The extent of injury is influenced by
the severity of the traumatic event (5)
and the presence or absence of
protective gear such as mouth guards,
face shields, airbags and seatbelts.
Direction of force against the teeth and
supporting structures and the type of
impact blunt or sharp also can determine
how much tissue damage will result. It
is well recognized that preventive
measures significantly reduce the
severity of injuries (6). The quality
and timeliness of initial care
contribute to a desirable outcome by
promoting healing. A good example is the
avulsed tooth: if it is replanted within
the first few minutes after avulsion,
the prognosis is good; with a high rate
of success (7). It is important to note,
however, that the quality of initial
care also is important. The initial
treatment should not add more traumas to
already injured tissues (8). An example
of this principle is with respect to
luxated teeth: the repositioning of
displaced teeth and adjacent tissues
must be done very gently to promote
desirable wound healing and long-term
favorable outcome. Follow-up evaluation
and care are important components of
long-term successful outcomes(5). A
replanted avulsed tooth may show an
excellent initial healing response of
the severed periodontal ligament but if
the necrotic pulp is allowed to harbor
bacteria, the resultant root resorption
will lead to loss of the tooth. Often
the long-term outlook for a traumatized
tooth is related to the response of the
tooth's pulp, thus the importance of
endodontic considerations in dental
trauma(9). Acute dental injury can be a
very costly problem for a given society,
as in the form of direct costs (e.g.
manpower involved, materials used) and
indirect costs to the patient (e.g. lost
income due to loss of working hours,
long observation periods, and renewed
treatments), better understanding of the
healing processes following injury might
enable the practitioner to create a
biologically sound (and possibly more
economical) treatment strategy which is
based on principles of wound healing and
provide a more conservative, less
aggressive treatment in selected cases
(1).
Dental trauma
An acute dental trauma may imply impact to the hard dental tissues and damage to
the pulp and periodontium, including the
surrounding alveolar bone. In the case
of luxation injuries, the trauma often
results in rupture of the neurovascular
supply at the level of the apical
foramen(1). From the moment of impact,
wound healing processes are initiated
aiming at repair (e.g. pulp canal
obliteration) or regeneration (e.g. pulp
survival) of the damaged tissues.
Unfortunately, these attempts at
healing are often unsuccessful
ultimately leading to partial or total
pulp necrosis and/or root resorption(1).
Classification of dental injuries
Comparing and accumulating data from
different studies is extremely difficult
due to the differences in the
definitions and classifications used
(See Table 1).
Andreasen's
classification(10) contains 19 groups
and includes injuries to the teeth,
supporting structures, gingiva and oral
mucosa. Whilst this classification is a
modification of the World Health
Organization's (WHO) classification,
(11) it is a more comprehensive system
that allows for minimal subjective
interpretations. The WHO classification
of oral trauma describes injuries to the
internal structures of the mouth.
Luxation injuries are grouped as one and
not divided into intrusive, extrusive
and lateral luxations as is the case
with the Andreasen classification.
Injuries to the alveolar socket and
fractures of the mandible or maxilla are
not grouped under oral injuries with the
WHO standards, but rather are classified
separately as fractures of face bones.
There is a broad group incorporated with
the WHO standards which allows for
'other injuries, including laceration of
oral soft tissues'. These types of open
ended groupings may lend themselves to
misinterpretation by investigators.
The Ellis classification(12) is another
modification of the WHO system which has
been used by various authors for
recording dental trauma. This system is
a simplified classification which groups
many injuries and allows for subjective
interpretation by including broad terms
such as 'simple' or 'extensive'
fractures. Injuries to the alveolar
socket and fractures of the mandible and
maxilla are not classified here. Whilst
there are numerous classification
systems currently available, some
investigators have opted to record only
specific injuries, hence creating their
own classification and augmenting the
difficulties when comparing studies(12).
Luxation Injuries and their Endodontics Consideration
This category of dental injuries
includes impact trauma that ranges from
minor crushing of the periodontal
ligament and the neurovascular supply of
the pulp to more major trauma such as
forceful and sometimes total
displacement of teeth (avulsion)(9).
Injury to a tooth supporting structure
seldom spares the pulp from trauma. Only
in cases of minimal trauma does the pulp
have a good chance of recovering.
Otherwise, when a tooth is impacted by a
blow, the force is very likely to damage
the vasculature entering the apical
canal opening, with the result that the
pulpal blood supply is compromised (13,
14). Tooth luxation (not including
avulsion) comprises 30 to 44% of dental
trauma (14). These figures are probably
on the low side since many cases of mild
luxation are not reported. In severe
injuries, luxations may go unnoticed in
the face of more obvious injuries.
Besides pulpal injuries, impact trauma
may also affect the tooth's periodontal
support. Loss of attachment, if not
restored by subsequent repair, will
result in pocket formation and reduction
in tooth support. The goal in treatment
of luxation injuries is to promote
recovery of both pulpal and periodontal
health; realistically, except in young,
immature teeth, pulpal recovery is not
as likely to occur as periodontal repair
(15).
A frequently overlooked cause of luxation injuries, including avulsions, occurs
during intubation in the operating room.
Damaged teeth were the most frequent
anesthesia-related insurance claim(16).
Examination and Diagnosis
There are five types of luxation
injuries and these are (17):
Concussion: The tooth is
sensitive to percussion only. There is
no increase in mobility, and the tooth
has not been displaced. The pulp may
respond normally to testing, and no
radiographic changes are found.
Subluxation: Subluxation injuries include teeth that are sensitive to
percussion but also have increased
mobility. Often sulcular bleeding is
present, indicating vessel damage and
tearing of the periodontal ligament.
There is no displacement and the pulp
may respond normally to testing.
Radiographic findings are unremarkable.
(Fig.1 A).
Extrusive luxation: These teeth have been partially displaced from the
socket along the long axis. Such
extruded teeth have greatly increased
mobility and radiographs show
displacement. The pulp usually does not
respond to testing. (Fig.1 B).
Lateral luxation: Trauma has displaced the tooth lingually, buccally,
mesially, or distally; that is out of
its normal position and away from its
long axis. If the apex has been
translocated during the displacement,
the tooth may be quite firm. Percussion
sensitivity may or may not be present
with a metallic sound if the tooth is
firm, indicating that the root has been
forced into the alveolar bone (Fig.1 C).
Intrusive luxation: Teeth are forced into their sockets in an axial
(apical) direction, at times to the
point of being buried and not visible.
They have decreased mobility and
resemble ankylosis (Fig.1 D). Concussion
injuries generally respond to pulp
testing. Because the injury is less
severe, pulpal blood supply is more
likely to return to normal. Teeth in the
subluxation in young, immature teeth,
pulpal recovery is not as injury group
also tend to retain or recover pulpal
responsiveness but less predictably than
teeth with concussion injuries. In both
cases, an immature tooth with an open
apex has a better prognosis. Extrusive,
lateral, and intrusive injuries involve
more displacement and therefore more
damage to apical vessels and nerves.
Therefore pulp responses in teeth with
extrusive, lateral, and intrusive
luxations are often absent. These pulps
often do not recover responsiveness even
if the pulp is vital (has blood supply),
because sensory nerves are permanently
damaged. Exceptions are immature teeth
with wide open apices; these teeth often
regain or retain pulp vitality
(responsiveness) even after severe
injuries (13,18).
Radiographic evaluation: The initial radiograph made after the injury will
not disclose the pulp condition.
However, it is very important for
evaluation of the general injury to the
tooth and alveolus and serves as a basis
for comparison of subsequent
radiographs. Evidence of resorption,
both internal and external, and
periradicular bony changes is sought.
Resorptive changes, particularly
external changes, may occur soon after
injury; if no attempt is made to arrest
the destructive process, much of the
root may be rapidly lost. Inflammatory
resorption can be intercepted by timely
endodontic intervention(17). Pulp space
calcification or obliteration is a
common finding after luxation injuries
(19). This condition called calcific
metamorphosis; and the canal
obliteration may be partial or nearly
complete (after several years) and does
not require root canal treatment, except
when other signs and symptoms indicate
pulp necrosis (17).
Treatment of luxation Injuries
For concussion injuries, no immediate treatment is necessary.
The patient should allow the tooth to
"rest" (avoid biting) until sensitivity
has subsided. Pulp status is monitored.
Subluxations may likewise require no
treatment unless mobility is moderate;
stabilization may be necessary if
mobility is of grade 2 (15). Extrusive
and lateral luxation injuries require
repositioning and splinting. The length
of time needed for splinting varies with
the severity of injury. Extrusions may
need only 2 to 3 weeks, whereas
luxations that involve bony fractures
need up to 8 weeks(17). Treatment of
intrusive luxation injuries depends on
root maturity (19). If the tooth is
incompletely formed with an open apex,
it may re-erupt. If it is fully
developed, active extrusion will be
necessary soon after the injury, usually
by an orthodontic appliance. In extreme
cases of intrusion, in which the tooth
has been totally embedded into the
alveolus, surgical repositioning may be
necessary(18). Tooth stabilization using
forcefully applied splints, such as
orthodontic bands results in further
injury to the traumatized periodontium
and pulp. Hence a gently applied splint
using the acid etch technique (like
orthodontic braces) is to be preferred.
Antibiotic treatment did not improve
pulp survival. While the value of
complete or incomplete repositioning
could not be established from these
studies, there was a tendency towards
more pulp necrosis following complete
repositioning. Oral rinsing with saline
prior to repositioning might thus
improve treatment success, as it does
following replantation of avulsed
incisors (15). A tooth with any luxation
injury showing signs or symptoms of
irreversible pulpitis requires root
canal treatment; the procedure is
conventional and may be completed in one
appointment. If the pulp is necrotic,
treatment may be accomplished in one or
two visits with calcium hydroxide placed
in the prepared canal for 1 to 2 weeks
before obturation. If there is evidence
of external resorption in addition to
pulp necrosis, calcium hydroxide should
be left in the canal until evidence of
root surface repair, such as
re-establishment of periodontal ligament
space, is evident(9). Andreasen in 1995
stated that particularly extruded and
laterally luxated incisors with
completed root development which
demonstrate coronal discoloration, loss
of pulpal sensibility, or radiographic
changes apically (luxations) or at the
line of root fracture could be observed
for pulpal repair over a longer period
of time (up to approximately 1 year) if
the following conditions are met:(1) 1)
The patient is at low risk of
inflammatory resorption (over 10 years
of age, has completed root formation and
has not suffered intrusive luxation). 2)
Neither prosthetic treatment nor
orthodontic therapy is planned to
immediately involve the injured tooth.
As the clinical and radiographic signs
described are assumed to reflect healing
processes within the pulp (and
periodontium), presumably due to
temporary disruption of the
neurovascular supply, the additional
trauma of crown preparation or
orthodontic tooth movement might be
anticipated to shift the balance of pulp
survival unfavorably. In the case of
planned orthodontic treatment, routine
radiographic controls during tooth
movement are recommended. 3) It is not
possible to adequately evaluate pulp
status following tooth luxation. Apart
from tenderness to percussion, none of
the present diagnostic criteria are able
to accurately reflect pulp status. Thus,
the possibility of asymptomatic sterile
pulp necrosis cannot be ignored. It is
therefore of utmost importance that the
patient be thoroughly informed about the
diagnostic problems involved and the
consequent need for extra follow-up
examinations and is willing and able to
cooperate. If there is any doubt as to
the possibility of recalling the
patient, endodontic therapy rather than
"observation therapy" should be the
treatment of choice.
Although it's rarely life-threatening, dental injuries can produce serious
esthetic problems as well as
psychological distress. Some fractures
and displacement may be difficult to
characterize without intra-oral
radiography, which is not available in
most emergency department settings. When
avulsions occur, re-implantation is most
appropriately accomplished by a dental
consultant. Physicians practicing in
isolated settings,
Conclusion
Although it's rarely life-threatening,
dental injuries can produce serious
esthetic problems as well as
psychological distress. Some fractures
and displacement may be difficult to
characterize without intra-oral
radiography, which is not available in
most emergency department settings. When
avulsions occur, re-implantation is most
appropriately accomplished by a dental
consultant. Physicians practicing in
isolated settings,
however, may be required to perform
rudimentary stabilization procedures. In
nearly all cases, time is of the essence
and follow-up with a dentist is
required.
References
Other
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Hyperplasia: Recent Advances
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