Internal replacement (invasive) resorption

This type of resorption is relatively rare
and may appear clinically as a pink area in the crown of the
affected tooth as shown in Fig 20a. However, the
clinician should recognize that a pink appearance in the
crown of a tooth is indicative of highly vascular
resorbing tissue which has removed sufficient dentine
and enamel to allow it to be visible through the thin
overlying tooth substance. While this may be internal in
origin, particularly if there has been a history of recent
trauma, it more commonly arises from an external
periodontal source. The location of the pink spot is
more likely to be entirely within the crown of the tooth
in internal replacement (invasive) resorption.

Hyperplastic invasive resorptions

The third group of dental resorptions are insidious in

nature and generally present complex therapeutic

challenges. In these cases, resorbing tissue invades the

hard tissues of the tooth in a destructive, and apparently

uncontrolled fashion, akin to the nature of some fibro-osseous 

lesions such as fibrous dysplasia.

An important distinguishing factor for this third group of

resorptions is that, unlike the first two types of

resorption, simple elimination of the cause of the lesion

is ineffective in arresting their progress. Total removal

or inactivation of the resorptive tissue is essential if

recurrence (or concurrence) is to be avoided.

Concurrence indicates the incomplete removal of the

resorptive tissue at the time of treatment and recurrence

is the re-establishment of the resorptive process. The

reason for recurrence or concurrence is probably due to

the invasive nature of the resorptive tissue whereby

small infiltrative channels are created within the  dentine

and these may interconnect with the periodontal

ligament in positions more apical to the main resorptive

defect.

Unless the tissue in these infiltrative channels is

inactivated the resorptive process will continue. While

these resorptions are not considered to be neoplastic,

their aggressive characteristics can seem to be similar.

At the present time one proven therapy for inactivation

is chemical in nature but surgical and other

technological modalities may also be applied.

These hyperplastic invasive resorptions may have a

pulpal (internal) or a periodontal origin (external).

Critical to the clinical use of therapies aimed at

controlling internal and external invasive tooth

resorptions is the correct diagnosis of the type and

localization of the resorption.

Hyperplastic resorptions may be subdivided into

internal replacement (invasive) resorption, invasive

coronal resorption, invasive cervical resorption and

invasive radicular resorption.

Communicating internal-external inflammatory resorption

Where resorption has extended from an internal

inflammatory resorption to involve the external surface

a communicating lesion is created. This can be

recognized radiographically by a radiolucency within

the tooth structure extending to the exterior surface

and the surrounding bone. While treatment is possible,

it is complex and referral to an endodontist is suggested

or implant therapy could be considered.

External inflammatory root resorption

Classically, this type of external root resorption

occurs when infection is superimposed on a traumatic

injury – usually following replantation of an avulsed

tooth or a luxation injury. Nevertheless it can also be

induced in some cases of endodontic pathosis as shown

in Fig 15a. Despite the degree of external inflammatory

resorption, treatment can be successful (Fig 15b).

A prerequisite for external inflammatory root

resorption is damage to the normally protective

Internal inflammatory (infective) root resorption

Internal inflammatory resorptions may be 
classified according to location as: (1) apical and (2)
intraradicular.
(1) Apical
A recent study has shown that apical internal
inflammatory resorption is far more common in teeth
with various inflammatory periapical pathoses than
previously thought.

The study showed that 74.7 per
cent of teeth with periapical lesions had varying degrees
of apical internal resorption, ranging from slight 
(grade 1) to severe (grade 4). Radiographically, apical
internal resorption may be difficult to diagnose when
the resorptions are of the lower grades as described by
Vier and Figueiredo, but should be discernable in
grades 3 and 4 lesions. This study has important
clinical implications in root canal preparation.

Infection induced dental resorption

The response of the dento-alveolar apparatus to

infection is characterized by inflammation which may

result in tooth resorption. This may be a consequence

of infective endodontic pathosis alone or superimposed

on trauma induced resorption. These infection induced

resorptions, which are generally termed inflammatory

root resorptions, may occur as internal resorptions,

external resorptions or combined internal-external

lesions. These infection induced resorptions can vary

widely in complexity but will generally respond

favourably to therapy aimed primarily at removing the

infective agent. Additional impetus to resorption

control can be provided by the use of anti-clastic

therapeutic agents such as Ledermix Paste (Lederle

Pharmaceuticals Wolfratshausen Germany) used as

Replacement resorption

The most serious form of trauma induced non-infective 
root resorption is  replacement resorption
which, as the name suggests, involves the progressive
replacement of tooth structure by alveolar bone and
ultimately tooth loss. Replacement resorption follows
the death of viable periodontal ligament cells due to
factors such as compression or drying of the ligament
cells as in the case of delayed replantation of an avulsed
tooth. On rare occasions an intact cementum/

Pressure resorption and orthodontic resorption

More extensive trauma induced non-infective root
resorption may be induced by the pressure of a crypt of
an unerupted/erupting tooth or some neoplasms and
more commonly during orthodontic treatment. The
resorption is often extensive and easily observable
radiographically. Figure 6 shows the radiographic
appearance of extensive resorption of a maxillary

Surface resorption

From a treatment management point of view, the

simplest form of trauma induced (non-infective)

resorption is surface resorption which, as the name

suggests, is a shallow resorption of cementum often

with involvement of a small amount of underlying

dentine. This type of resorption is self-limiting and

transient and can follow some traumatic injuries or

Trauma induced tooth resorption

In this category using a broader interpretation of the

term “trauma”, resorptions may have resulted from

pressure from unerupted or erupting teeth or some

neoplasms, from biomechanical forces involved in

orthodontics, mechanical trauma (luxation and avulsion

injuries) and surgical, thermal or chemical trauma.

Classification of dental resorptions

Classifications play an important role for the
clinician in the process of diagnosis and treatment
planning. Andreasen has over the past 40 years made
an unique contribution to the understanding of tooth
resorption following dental trauma and his original
classification which follows (Fig 1) remains the most
widely accepted.

Management of tooth resorption

A correct diagnosis and an understanding of the

aetiology and dynamics of the processes involved in

tooth resorption is critical to effective management.

Tooth resorptions can be classified as: (1) trauma

induced; (2) infection induced; or (3) hyperplastic

invasive. Some transient trauma induced resorptions

require no treatment but must be carefully

monitored to check that there are no complicating

issues such as infection. In cases of trauma induced

replacement resorption, a multidisciplinary approach

is usually necessary to ensure an optimal long-term

solution. Infection induced tooth resorptions require

the removal of the invading micro-organisms by

endodontic therapy including intra-canal medication

which can also facilitate repair of the resorbed tooth

structure. The hyperplastic invasive tooth resorptions

pose considerable challenges in management due to

the complexity and aggressive nature of the

resorptive process. With careful case selection and

complete inactivation of resorptive tissue successful

management can be achieved.

Management of pulp and root canal conditions

The ultimate decision the practitioner must make is

whether to treat or not to treat the tooth, and if treat-ment is indicated, 

whether to treat the pulp or the root

canal system. The alternative management is to extract

the tooth and then to consider a prosthesis to replace it.

Accurate diagnosis and identification of the cause(s) of

the problem(s) will lead to effective management of the

offending tooth. Table 5 

summarizes the treatment strategies for the management of the various pulp

diseases.

Management strategies vary considerably for the

various pulp conditions which emphasizes the need for

an accurate diagnosis before considering any treatment.

Conditions such as a pulp with atrophy or pulp canal

calcification do not require any treatment (unless the

pulp has become necrotic and the canal has been

infected). A conservative approach should be adopted

when dealing with conditions such as pulp necrosis

without infection since pulp tests are not entirely

Examination and diagnostic procedures to assess the status of the pulp and root canals

The importance of gathering all the relevant

information for making a correct diagnosis cannot be

over-emphasized. An accurate diagnosis is imperative in

all cases so appropriate treatment can be provided in a

timely manner.

A current medical and dental health history is

important, not only for preventing health problems

during treatment but also to help reach a thorough

diagnosis.

For example, pain medication taken within

6–12 hours prior to examination may alter the

responses to pulp sensibility tests or other clinical tests.

One tablet of pain medication may be sufficient to

reduce the pulp or periapical inflammation, or the

analgesic may alter the patient’s perception of pain by

lowering the pain threshold.

Periapical diseases

A discussion about pulp diseases would be

incomplete without discussing the periapical tissues and

their disease processes since periapical diseases are

usually a direct result of pulp diseases. It is beyond the

scope of this paper to discuss periapical diseases in

detail and such diseases have been fully discussed in

other publications.

Unfortunately, there is also

considerable confusion amongst authors and clinicians

regarding the classifications and terminology used for

periapical conditions.

However, Abbott has 

outlined a classification for periapical diseases that is

based on the same principles as the above classification

for pulp diseases and root canal conditions and

therefore the two classifications can be used

concurrently.

When a tooth is being examined for pulp disease, the

condition of the periapical tissues must also be

assessed, and vice versa, since apical periodontitis is

usually associated with inflammatory conditions of the

pulp (i.e., reversible and irreversible pulpitis), or

infection of the pulp space following necrosis of the

pulp or after previous endodontic treatment. That is,

periapical diseases are usually a direct consequence of,

and/or a sequel to, interaction with the root canal

system.

Examples of some typical diagnoses are:

• Acute irreversible pulpitis with primary acute apical

periodontitis due to caries.

• Acute irreversible pulpitis with primary acute apical

periodontitis due to breakdown of a restoration 

(Fig 3).

• Necrotic and infected pulp with primary acute apical

periodontitis due to caries and restoration break-down.

• Pulpless, infected root canal system with secondary

acute apical periodontitis due to breakdown of the

restoration.

• Pulpless, infected root canal system with a chronic

apical abscess due to breakdown of the restoration

(Fig 5).

• A pulpless, infected root canal system with secondary

acute apical periodontitis due to breakdown of the

restoration (Fig 6).

• A root-filled tooth with an infected root canal system

and chronic apical periodontitis due to breakdown

of the restoration (Fig 6).

• Pulpless, infected root canal system with chronic

apical periodontitis due to a crack in the tooth and

caries.

• A clinically normal pulp with pulp canal calcification

but no signs of apical periodontitis (Fig 7a).

Endodontically-treated teeth

Many teeth that are examined by dentists will have

had previous pulp therapy or endodontic treatment.

Such treatments include pulp capping, partial pulpotomy,

pulpotomy, partial pulpectomy and pulpectomy. These

teeth may or may not have signs or symptoms, and they

may or may not have apical periodontitis associated

with them. The technical standard of the previous

treatment may also vary considerably and this can only

be partly assessed by the radiographic appearance of

the material(s) placed in the pulp space or root canal(s).

Essentially, the radiographic appearance of a root

filling only indicates the radiodensity of the material

and where the material has been placed. Radiographs

do not provide any indication of whether or not the

root canal system was disinfected during the previous

treatment, how effectively the canal was sealed,

whether the seal has been maintained, whether any

bacteria survived the previous treatment and whether

any new bacteria have entered the root canal system

since the treatment was completed.

Degenerative changes

The pulp will usually respond to noxious stimuli by

becoming inflamed, but it may also respond by

degeneration which includes atrophy and fibrosis,

calcification, root resorption, or hyperplasia.

Atrophy

Atrophy is a normal physiologic process that occurs

with age and is asymptomatic. Pulp sensibility tests

responses may be normal or delayed. No significant

radiographic or clinical signs are present. As the pulp

atrophies, there will also likely be fibrosis of the pulp

tissue and the extent of this will be largely determined

by the number of irritant episodes suffered by that

particular pulp throughout its history. The size of the

pulp chamber may be reduced. No treatment is

required.

Pulpless and infected root canals

Pulpless canals will always be infected. There will be
no pain from the tooth itself when it has a pulpless
canal, although some patients may give a history of
occasional vague discomfort over a period of time.
However, pain may arise from the periradicular tissues
that become inflamed because of the presence of
bacteria in the pulp space. The only clinical sign
suggesting the condition may be the lack of response to
pulp sensibility tests. No significant changes can be
detected on the radiograph in the early stages of this
condition but within 2–10 months there will be a
radiolucency suggesting periapical involvement.

As there is the potential for erroneous pulp sensibility test
responses, corroborating the clinical findings, radio-graphs 
and patient information is necessary for a
definitive diagnosis.

Pulp necrosis

A necrotic pulp should be suspected when the tooth

does not respond to pulp sensibility tests. However, this

will not always be the case since teeth with pulp canal

calcification, previous root fillings or pulpotomies will

also not respond to pulp sensibility tests. Likewise,

some teeth or patients just do not respond to such tests

for no apparent reason. When pulp necrosis is present,

the history may reveal past trauma, previous episodes

of pain or history of restorations and caries.

Radiographically, a tooth with a necrotic pulp may

have signs (such as untreated caries, an extensive

restoration, previous pulp capping) or there may be no

such signs (e.g., following trauma). Trauma to a tooth

may cause pulp necrosis as a result of severing the

apical blood supply if the tooth has been displaced

from its normal position (e.g., luxations, avulsion) or if

there has been significant damage and inflammation to

the apical periodontal ligament (e.g., subluxation).

No significant radiographic changes are evident at

the root apex unless there is also periapical involve-ment, 

and this only occurs once the necrotic tissue

becomes infected. It is important to realize that a

necrotic pulp  per se does not cause apical periodontitis

unless it is infected.

Necrobiosis

A tooth with necrobiosis has both inflamed and

necrotic (usually infected) pulp tissue.

Many dentists use the term “partial necrosis” for this stage of the

disease process; however, “necrobiosis” was suggested

by Grossman

because it more accurately indicates the

condition – the key factor to the spread of the disease

process is the presence of bacteria within the necrotic

part of the pulp rather than the necrosis itself of part of

the pulp. The necrotic tissue may be in the coronal

portion of the pulp (e.g., pulp chamber) with the

inflamed tissue apically, or the different tissue states

may exist in different canals of a multi-canal tooth.

Teeth with this condition can be quite difficult to

diagnose since they usually present with a mixture of

the signs and symptoms of both pulpitis and necrosis

with infection. The symptoms may be mild with

Irreversible pulpitis

One of the classic symptoms of irreversible pulpitis is

lingering pain induced by thermal stimuli. Only mild

temperature changes are required to induce the pain

(e.g., tap water, breathing cold air). The initial reaction

is a very sharp pain to hot or cold stimuli and it then

lingers for minutes to hours after the stimulus is

removed. The lingering pain is usually a dull ache or a

throbbing pain. Spontaneous (unprovoked) pain, which

may wake the patient at night and may become worse

when lying down, is another hallmark feature of

irreversible pulpitis. Patients with irreversible pulpitis

often need strong analgesics and may have difficulty

locating the precise tooth that is the source of the pain.

They may even confuse the maxillary and mandibular

arches (but not the left and right sides of the mouth)

because of the extensive branching of dental nerve

axons and perhaps fewer proprioceptive fibres in the

pulp.

Reversible pulpitis

A pulp with reversible pulpitis has mild inflammation
and it is capable of healing once the irritating stimulus
has been removed. Pain is only felt when a stimulus
(usually cold or sweet foods but sometimes heat) is
applied to the tooth, and the pain ceases within a few
seconds or immediately upon removal of the stimulus.
The pain is short and sharp in nature but not
spontaneous. There are no significant radiographic
changes evident in the periapical region, and the only
radiographic findings of note may be the cause of the
problem, such as caries, a deep restoration, etc. Usually
more extreme temperatures are required to induce the
pain rather than mild changes (e.g., ice cream rather
than tap water).

Clinically normal pulp

The term “clinically normal pulp” is used to classify

a pulp that has no signs or symptoms to suggest that

any form of disease is occurring. The term “clinically”

is used since such a pulp may not be histologically

normal and/or may have some degree of fibrosis

(scarring) as a result of previous injury or stimuli.

A clinically normal pulp is asymptomatic. It

produces a mild and transient response to various

stimuli but the nature and severity of the response may

vary according to the age and state of the tooth. As

long as there has been no calcification of the coronal

pulp space, a clinically normal pulp will react to cold

stimuli with mild pain that lasts for no more than 1–2

seconds after the stimulus is removed. A clinically

normal pulp does not respond to heat stimuli.

Percussion and palpation tests will not elicit any

tenderness. Radiographic examination will demonstrate

normal appearance of the pulp chamber, root canals

and periapical tissues.

Signs and symptoms of pulp and root canal conditions

Diseases of the pulp tissues are dynamic and
progressive in nature (Fig 1). Each disease condition may
progress to other conditions if left untreated. Hence, the
signs and symptoms will vary depending on the stage of
the disease at the time the patient presents for treatment.
In addition, the reaction to and the perception of pain
will vary between individual patients and is influenced
by the individual’s emotional status and the coping
strategies used to manage the pain. Many of the signs
and symptoms overlap between the various pulp
conditions due to the dynamic interactions and the
progressive nature of the disease process. Therefore, the

A clinical classification of the status of the pulp and the root canal system

Many different classification systems have been

advocated for pulp diseases. However, most of them

are based on histopathological findings rather than

clinical findings which leads to confusion since there

is little correlation between them. Most classifications

mix clinical and histological terms resulting in

misleading terminology and diagnoses. This in turn

leads to further confusion and uncertainty in clinical

practice when a rational treatment plan needs to be

established in order to manage a specific pathological

entity. A simple, yet practical classification of pulp

diseases which uses terminology related to clinical

The endodontic management of traumatized permanent anterior teeth: a review

The endodontic management of traumatized

permanent anterior teeth has been reviewed and

recommendations have been presented for each type of

injury. The management of dental injuries is an

evolving science. Some traditional treatment options

have stood the test of time and are still valid to this day.

Others have been reviewed and modified with the

passage of time, as new science and new materials

evolve to prove, disprove or facilitate approaches to the

management of these injuries. Practitioners need to

always be aware of changes that occur from time to

The immature tooth with pulp necrosis and infection

A large number of different apical configurations can

result if an immature tooth with an open apex is

traumatized. Continued root development, apical

doming, in-growth of bone, and aberrant root formation

have all been reported. Repair appears to be more

related to the creation of an environment conducive to

repair rather than the type of medicament used.

The diagnosis of pulp necrosis and infection in an

immature tooth is often difficult. Radiographic changes

may be difficult to see. The clinician often has to rely

on an assessment of other signs and symptoms, such as

the presence of acute or chronic pain, tenderness to

percussion, increased mobility, discolouration of the

crown, or the presence of a draining sinus tract.

Endodontic treatment of teeth with pulp canal calcification

Treatment of teeth with pulp canal calcification

presents a dilemma. A number of authors have

proposed that for endodontic technical reasons and for

prevention of tooth discolouration, these teeth should

be root filled once the calcification process is detected.

Endodontic procedures are certainly easier if under-taken at this stage. 

However, most of the recent

literature indicates that endodontic treatment is

unnecessary unless the tooth is symptomatic or there is

radiographic evidence of pulp necrosis and infection–

i.e., a periapical radiolucency. Proponents of the latter

course of action base their opinions on histological

studies which indicate that the calcific changes do not

warrant pulp extirpation and that a remnant of the

canal is always present.

Pulp canal calcification

Calcification of the root canal (commonly referred to

as pulp canal obliteration, or PCO) is a common sequel

following luxation injuries to permanent teeth,

particularly teeth that have been injured before their

root formation has been completed.

Abbott and Yu have discussed the terminology regarding this condition

and they have recommended the use of the term

“calcification” (rather than “obliteration”) as it more

accurately describes what is happening, or what has

happened, within the root canal. Obliteration implies

complete blocking or elimination of the canal which is

unlikely, even in a tooth that radiographically appears

to have no root canal present.

Clinically, a yellowish discolouration of the crown

may be observed. Pulp canal calcification is also a

common occurrence in root-fractured teeth occurring

principally in the region of the fracture, and in the

apical fragment. It may also occur in teeth associated

with alveolar and jaw fractures. 

Endodontic treatment of teeth with resorptive defects

Surface resorption is self-limiting and does not

generally require treatment. Frequent clinical and

radiographic review is necessary, however, to confirm

that inflammatory and replacement resorption are not

occurring in these teeth.

Where resorption has been initiated in traumatized

teeth, replacement resorption cannot be treated

effectively. Nevertheless, as replacement and

inflammatory root resorption can occur together,

endodontic therapy to remove necrotic and infected

pulps from resorbing teeth is warranted. As an interim

measure the teeth can be dressed with a cortico-steroid/

antibiotic paste or calcium hydroxide, or it can

be root filled. Each case has to be treated on its merits.

Treatment of resorbing traumatized ankylosed anterior

teeth often requires multi-specialty treatment planning.

Before extensive endodontic management is

contemplated, the options of extraction, prosthetic

replacement, maintenance of the space for future

prosthetic replacement, orthodontic space closure,

Root resorption

Resorption is a common sequel to dental trauma and

may be caused directly by the traumatic incident or

indirectly through subsequent infection. Andreasen has

described three types of resorption following trauma:

surface resorption, replacement root resorption and

inflammatory root resorption.

Root resorption has also been described as being 

as ankylosis-related and

infection related.

Heithersay has extensively reviewed

root resorption and proposed a new system of

classification of these defects, as well as describing a

range of treatment options for these lesions.

Endodontic treatment of avulsed teeth

It has been previously recommended that in mature

teeth, endodontic therapy should be commenced seven

to 10 days following replantation.

However, it would now seem that pulp extirpation should be

carried out as soon as possible to prevent the initiation

of inflammatory root resorption.

The canal should be

debrided, dressed with a corticosteroid/antibiotic or

calcium hydroxide paste preparation for one to three

months, after which time the canal can be obturated

and the access cavity sealed. Follow-up radiographs

should be taken at regular intervals of one, three, six

and 12 months.

Stage of root development

The replantation of avulsed teeth with immature root

development has been the subject of review.

As the pulps in a small percentage of replanted immature teeth

may survive, it is recommended that endodontic

treatment should be delayed in these teeth to establish

whether root formation continues. Revascularization

appears inversely proportional to root length. However,

external inflammatory resorption progresses very

rapidly in immature tooth roots. Thus, regular clinical

and radiographic examinations at short intervals are

recommended to establish whether resorptive processes

have been initiated. Great care should be taken in

Contamination of the root surface

Contamination of the root surface has been found to

be a prognostic indicator for root resorption. The

prevalence of resorption in teeth replanted without

visible contamination has been reported to be 57 per

cent, whereas 75 per cent of teeth that were washed and

87 per cent of those that were rubbed clean underwent

resorption. When teeth were replanted with visible

contamination still present, 100 per cent exhibited

resorption.

Effect of endodontic therapy

Endodontic therapy involving obturation with gutta-percha or 
the placement of calcium hydroxide dressings
at the time of replantation delays periodontal healing
and hastens replacement resorption in mature teeth.
Endodontic therapy should be delayed until the initial
period of soft tissue healing takes place.

However,since revascularization rarely occurs in mature teeth,
and as pulp necrosis contributes to inflammatory root
resorption, it has been recommended that in mature
teeth pulps should be extirpated as soon as possible

Antibiotic therapy

Systemic administration of antibiotics is generally

recommended in order to prevent the harmful effects of

bacterial contamination, although the evidence to

support this is limited. Experimental animal studies

have reported that systemic antibiotics decrease the

incidence of inflammatory root resorption but have a

limited, or no, effect on the pulp.

Recent research has

focused on the effect of topical antibiotic therapy with

promising results in animal models. Topical doxycyline

and minocyline applied to the root surface before

replantation have been found to increase the chance of

pulp revascularization in dogs and to decrease the

chance of inflammatory root resorption and ankylosis

Socket preparation

Transplantation experiments indicate that the vitality

and integrity of the tooth socket is a factor to be noted

in the development of root resorption, although the

length of time out of the socket appears to be more

critical. Curettage of the socket is not necessary,

although doing so has no major effect on the replanted

tooth. However, gentle irrigation of the socket to

remove any blood clots prior to replantation is thought

to be better than curettage and may be necessary if

there has been a time delay in replanting the tooth.

Splinting

Splinting procedures do not significantly improve

periodontal healing. Longer splinting times (greater

than 10 days) tend to hasten the resorption process,

particularly if inflexible splints are used. It is probable

that functional stimulation plays a role in repair.

Storage medium

As most avulsed teeth are not replanted at the site of

the injury and few patients can receive treatment within

15 minutes, a suitable storage medium to maintain the

health of the periodontal ligament cells is critical. In

studying periodontal ligament healing associated with

replanted teeth in monkeys, 

Andreasen varied the extra-alveolar time periods and the storage media. He

established that if the teeth cannot be replanted

immediately, then storage in saliva or saline solutions

significantly reduced the amount of root resorption.

Extra-oral time

It has been clearly established that the length of

extra-oral dry time and the stage of root development

are the most critical factors associated with root

resorption.

The critical dry time where a statistically

significant increase in root resorption was observed

was 15 minutes in one study although just five minutes

of dry time was sufficient to increase the incidence of

resorption in another study.

Teeth that are replanted

immediately have the best long-term prognosis and the

least incidence of root resorption. 

One animal study

Vitality of the periodontal ligament and tooth socket

Vitality of the periodontal ligament cells is a factor

that greatly affects the healing of replanted teeth. When

the vitality of the periodontal ligament cells is lost,

replacement resorption usually occurs. There is a

relationship between the total area of root surface

where the cells have become necrotic and the amount of

replacement resorption generated.

Avulsion

Avulsion or exarticulation occurs when a traumatic

injury totally displaces a tooth from the socket.

Treatment of the avulsed tooth is one area in dentistry

where recent research has been applied to greatly

improve the prognosis for the long-term retention of

these teeth. Andreasen recently reviewed tooth avulsion

and replantation.

Although the prognosis for an

avulsed tooth must always be guarded, replantation as

soon as possible followed by a brief period of flexible

Endodontic treatment of luxation injuries

It is generally agreed that for most luxation injuries,

with the exception of intrusive injuries in mature teeth,

endodontic therapy should be postponed until

additional signs of necrosis appear such as colour

change and radiographic changes, both in the tooth and

the surrounding bone.

Should the pulp become

necrotic and infected, treatment is dependent upon the

state of closure of the apex. If apical maturation is

complete, standard endodontic treatment is indicated.

Should apical development be incomplete, apexification

procedures utilizing calcium hydroxide

and/or MTA are indicated.

The first concern in the treatment of luxation injuries

should be the repair of the periodontium. Soft tissue

injuries and repositioning should be treated before

endodontic procedures are contemplated. 

Endodontic treatment need not be considered for

concussion and subluxation injuries until there are

signs of pulp necrosis. However, judicious grinding may

be necessary to free the tooth from occlusion. Frequent

radiographic examinations and pulp sensibility testing

are needed during the follow-up period. 

If the root is extruded, careful monitoring of the

tooth must be undertaken after repositioning and a

period of splinting of two weeks duration. In the event

that there has been a delay in repositioning the teeth,

gentle orthodontic treatment may be needed to

reposition them. Radiographic examination and pulp

sensibility testing should be carried out at regular

intervals such as: two weeks, one month, two months,

six months, 12 months and then on a yearly basis for a

number of years.

Endodontic therapy should be commenced immediately there is evidence of pulp

necrosis or root resorption. While immature teeth can

revascularize and can continue root development,

which can be seen radiographically, it is not prudent to

delay treatment in immature teeth that show any sign

of root resorption, as inflammatory root resorption can

occur very rapidly. A delay in treatment even for one

week can result in loss of substantial tooth structure. In

these teeth, pulp extirpation and root filling after

calcium hydroxide or corticosteroid/antibiotic therapy

is the treatment of choice. In mature teeth, endodontic

therapy should be undertaken where there is clinical

and/or radiographic evidence of pulp necrosis and

infection, or root resorption. Continued lack of

reaction to pulp sensibility testing is usually indicative

of pulp necrosis, unless there is radiographic evidence

of ongoing calcific changes in the root canal system.

Where a tooth has been laterally luxated, it should be

repositioned without delay. Again, endodontic therapy

is carried out only when there are signs of pulp necrosis

or root resorption. Lateral luxation does not occur

without fracture of the alveolar socket. Immediate

repositioning, with forceps if necessary, and splinting 

is therefore recommended. Splinting should be of 

four weeks duration to allow the fractured bone to

heal.

Treatment of intruded teeth can be a challenge. Pulp

necrosis almost invariably occurs in intruded mature

teeth and treatment can complicated by the fact

that most intruded teeth are also associated with crown

fractures.

Subsequent re-eruption, if it occurs, may be

very slow during which time root resorption may

become advanced. Delayed repositioning leaves roots in

intimate contact with bone and this influences the onset

of replacement resorption. Thus, mature teeth should

be repositioned as soon as possible and the pulps

removed immediately, or as soon as possible once the

soft tissues have healed sufficiently to do so, to help

prevent the onset of inflammatory root resorption.

22,74

Repositioning intruded teeth is a priority and can

occur through spontaneous re-eruption or it may

require surgical or orthodontic repositioning. Surgical

repositioning or orthodontic repositioning is the

treatment of choice for mature teeth in adults (>17 years

of age).

A recent review found no significant

difference in healing between surgical or orthodontic

repositioning of permanent intruded teeth.

Surgical repositioning is preferred where there is complete

intrusion and gingival healing may prevent re-eruption

or complicate orthodontic repositioning. A surgical

technique may be more practical for multiple intrusions

where orthodontic anchorage may be an issue. Care

must be taken in repositioning these teeth to ensure that

the hard tissues are brought down with the tooth and

that the soft tissues are sutured into place if necessary.

While orthodontic extrusion has been advocated, it is

not always possible as the teeth are often wedged firmly

into the bone and attempts to extrude the tooth can

lead to intrusion of adjacent teeth. Each situation has to

be assessed on its merits and on the state of

development of the tooth. Mature teeth that are firmly

wedged into the alveolus should be immediately

repositioned surgically. In mature teeth, urgent

endodontic management should be commenced as soon

as practical following repositioning.

Intruded teeth with open apices are more likely to

erupt spontaneously and less likely to develop problems

of an endodontic origin. As immature intruded teeth

can spontaneously reposition themselves in the arch

and significantly better healing occurs when this

happens, it has been suggested that treatment be

delayed for these teeth.

However, if spontaneous repositioning does not appear to be occurring quickly,

immature teeth can be brought down by orthodontic or

surgical means as soon as possible after trauma. There

is an argument for surgically disimpacting these

intruded immature teeth from the alveolus to assist

with re-eruption. Regular radiographic follow-up at

two weeks, one month, two months, six months and

yearly is essential for these teeth as root resorption can

occur rapidly in immature teeth.

Should any resorption be detected, pulpectomy and treatment with calcium

hydroxide or a corticosteroid/antibiotic paste prior to

root filling procedures should be urgently carried out.

Surgical exposure of the intruded immature 

teeth to permit endodontic therapy has been proposed

to avoid delay in endodontic treatment and the

development of inflammatory root resorption.