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Root perforations: aetiology,
management strategies and
outcomes. The hole truth
S. Mohammed Saed,*1 M. P. Ashley2 and J. Darcey3
VERIFIABLE CPD PAPER
in this region. Typically this will follow an
aggressive crown-down approach with large
instruments such as Gates Glidden burs,
INTRODUCTION
A perforation is a communication that arises
between the periodontium and the root canal
space. Perforations can be pathological, result-
ing from caries or resorptive defects, but most
commonly occur iatrogenically (during or
after root canal treatment). Indeed, perfora-
tions occurring during root canal therapy
may account for as many as 10% of all failed
endodontic cases.1
AETIOLOGY
Iatrogenic perforations
Perforations of the coronal third:
Perforations of the coronal third often result
whilst attempting to locate and open canals
(Fig. 1). Calcications of the pulp chamber
and the orices, misidentication of canals,
significant crown-root angulations and
excessive removal of coronal dentine can
easily result in perforations in the coronal
or furcation regions.
Perforations of the middle third:
Strip perforations of the middle third may
occur if there is overzealous instrumentation
The purpose of this clinical article is to emphasise that root perforations can occur both during and after endodontic treat-
ment. These reduce the chance of a successful treatment outcome and can jeopardise the survival of the tooth. The aetiol-
ogy and diagnosis of root perforations are described. The article also focusses on the non-surgical and surgical manage-
ment of root perforations and describes how selection of the appropriate treatment depends on an accurate diagnosis.
used in narrow canals. It may also occur
during preparation of the canals, if les are
too large or the ling technique shapes the
1Dental Core Trainee, Oral and Maxillofacial surgery,
Bradford Royal Inrmar y; 2Consultant and Honorar y
Senior Lecturer in Restorative Dentistry, Associate
Clinical Head of Division, University Dental Hospital of
Manchester, Higher Cambridge Street, Manchester,
M15 6FH; 3Consultant and Honorary Lecturer in Re-
storative Dentistry, University of Manchester
*Correspondence to: S. Mohammed Saed
Email: sarasaed1234@hotmail.co.uk
Refereed Paper
Accepted 15 January 2016
DOI: 10.1038/sj.bdj.2016.132
©British Dental Journal 2016; 220: 171-180
• Explains the aetiology of root
perforations.
• Reviews factors associated with the
succes s of perforation repair.
• Discusses the management of
perforations.
• Highlights prevention strategies for
practitioners to follow.
IN BRIEF
PRACTICE
Fig. 1 In an attempt to locate the canal of
the 12 the dentist has perforated through
the buccal aspect of the tooth. The gures
clearly demonstrate the divergence of the
access cavit y from the canal structure
BRITISH DENTAL JOURNAL VOLUME 220 NO. 4 FEB 26 2016 171
© 2015 British Dental Association. All rights reserved
PRACTICE
canals too aggressively away from the centre
of the root. Classically, this occurs in curved
molar roots when the instrumentation is too
heavy on the inside curvature resulting in
a furcational strip perforation (Figs2a and
2b). Perforations of the middle third may
also occur during the pursuit of sclerosed
canals. In these instances the dentist may
need to use rotary or ultrasonic instruments
well into the root of the tooth risking lateral
perforation.
Perforations of the apical third:
Inadequate cleaning and shaping of the
canal can lead to blockages and ledges.
Once formed, these can cause instruments
to deviate, transporting the canal away from
the centre of the root, until a perforation
occurs. Stiff instruments placed into curved
canals may also straighten the canal, causing
zip perforations (Figs3a and 3b). An apical
perforation occurs when the clinician does
not respect the apical anatomy and passes
endodontic les too aggressively through the
apical constriction (Fig.4).
Post-space preparation:
Following obturation, careless post space
preparation may result in perforation.2
Traditional approaches to placement of post
retained restorations focus on achieving
good length and width for the post. This
creates the risk of both apical and strip per-
foration. Sometimes the post is not placed
into the root canal but the adjacent den-
tine, resulting in catastrophic consequences
(Fig.5).
Pathological perforations
These can result from root resorption or car-
ies. Root resorption is the progressive loss
of dentine and cementum by the continued
action of osteoclastic cells.3 When occurring
within the root canal system it is known as
internal inammatory root resorption. It
is seen radiographically as an oval shape
enlargement of the root canal system. The
exact cause is not known, but this process
can follow trauma, pulpal inammation
and pulpotomy procedures. Though the pro-
cess is uncommon and often self-limiting,
it can progress into a perforation. Thus,
early detection and intervention is essen-
tial to control the disease before such an
event occurs.4,5
External inammatory root resorption can
occur following damage to the cementum
and periodontal ligament cells on the root
surface. There are different types of exter-
nal resorption, but all have the potential to
continue until the resorptive defect com-
municates with the root canal (Fig.6). The
ability to control the resorption is dependent
upon the type, site and extent. Readers are
referred to more comprehensive papers on
the management of resorption.4,5,6
Extensive carious lesions can also lead to
perforations. These lesions are dened by
a destruction of dental tissues as a result
of microbial action. An untreated carious
lesion may either perforate the pulp chamber
oor or extend along the root, resulting in
perforation of the root. Treatment of these
perforations may require root canal treat-
ment, crown lengthening, and either root
extrusion or root resection in order to retain
valuable radicular segments. Unfortunately,
perforation in most of these cases renders the
tooth unrestorable.7
Fig. 2 Not only has an instrument fractured in the mesiobuccal canal of the 37 but there
has been a perforation of the middle third of the tooth in an attempt to remove and/or
bipass the instrument
Fig. 3 a) There is an acute cur ve distally in the apical region of the 24. b) This has not been
respected during instrumentation resulting in straightening of the canal and apical perforation
Fig. 4 A lack of control during the distal canal
preparation of the 46 has resulted in over
preparation and signicant over extension of
the gutta percha (as well as separation of an
instrument in the mesial canal)
Fig. 5 It’s a boy! A threaded post has been
placed though the furcation
Fig. 6 External cervical resorption of the 13.
The lesion has perforated into the pulp canal
space
172 BRITISH DENTAL JOURNAL VOLUME 220 NO. 4 FEB 26 2016
© 2015 British Dental Association. All rights reserved
PRACTICE
EPIDEMIOLOGY
The frequency of root perforations has been
reported to range from 3% to as high as
10%.1,8,9 However, as more complex endo-
dontic treatment cases are being attempted,
it is not an unrealistic expectation that there
will be an increased frequency of perfora-
tions in the future.1 According to Kvinnsland
etal.,2 53% of iatrogenic perforations occur
during insertion of posts, the remaining 47%
occur during routine endodontic treatment.
73% of all cases occur in the maxilla and
the rest in the mandibular arch. In maxillary
anterior teeth the study found that all perfo-
rations were located at the labial root aspect
due to the operator’s underestimation of the
palatal root inclination. In multi-rooted
teeth, however, furcation perforations may
occur whilst searching for the canal orices,
as dentine is removed from the pulpal oor.
DIAGNOSIS
Iatrogenic perforations are invariably iden-
tied from the profuse bleeding that fol-
lows the injury (Fig.7). This can often be
seen directly when a perforation occurs in
the coronal portion of the tooth, but some-
times, when a strip or apical perforation
occurs further within the canal, a paper point
inserted into the canal reveals the bleed-
ing. If no local anaesthetic is given, sudden
unexpected pain during treatment may also
indicate a perforation.
Apex locators are very useful in detect-
ing perforations. By placing the le onto
the perforation this will give a zero reading,
indicating a communication with the peri-
odontal ligament. Operating microscopes are
becoming increasing popular in identifying
perforations. The bright operating light and
magnication make it excellent for visualising
the position and extent of the perforation.
Radiographs can be used at the time of perfo-
ration, but do have their limitations: they are
only a two-dimensional representation and so
it may be difcult to accurately assess the site
and extent of the perforation. Taking a sec-
ond lm and shifting the radiographic beam
angulation to the mesial or distal aspect can
partly overcome this.
Late diagnosis of pathological perforations
is largely a combination of clinical assess-
ment, radiographs and the nature of the
presenting complaint. Untreated perforations
may be revealed by the presence of serous
exudate or sinus from the site of perforation,
sensitivity to percussion, localised periodon-
tal pocketing and chronic inammation of
the gingiva when the inammation has pen-
etrated the alveolar bone.10 In addition to the
methods described above, radiographs may
reveal radiolucent lesions that have devel-
oped since the perforation occurred, as there
may be local osteolysis (Fig.8).
Cone beam computed tomography is
increasingly important in the assessment of
perforations (Figs9a-c). There is evidence
that resorptive lesions and post perforations
can be accurately identied and assessed
using CBCT. These 3-dimensional scans are,
however, associated with increased exposure
to ionising radiation and as such, referral for
CBCT must only be considered if it could
change the clinical outcome.11 The presence
of pre-existing GP, posts and core restorative
materials will create artefacts and both the
referred patient and the practitioner must be
aware that this may compromise the diag-
nostic yield.
Sequelae and outcomes
Following the initial acute inammatory
response there may follow destruction of
periodontal bres, bone resorption and the
formation of granulomatous tissue. In the
mid and apical portions of the root this may
manifest as a radiolucency adjacent to the
perforation. If this is in close proximity to the
supra crestal attachment there may be pro-
liferation of epithelium and, ultimately, the
Fig. 7 Profuse bleeding resulting from a
perforation during endodontic access of the 15
Fig. 8 The post in the 45 perforates the mesial
aspect of the root wall. A periodontal pocket
has resulted from the chronic inammation
Fig. 9 a) A conventional lm of the 21 suggests there may be an aberrant access cavity.
b-c) CBC T conrms there is a perforation of the mid buccal aspect of the 21
BRITISH DENTAL JOURNAL VOLUME 220 NO. 4 FEB 26 2016 173
© 2015 British Dental Association. All rights reserved
PRACTICE
formation of a periodontal pocket (Fig.8).8
If the perforation is not detected early and
repaired, then the breakdown of the periodon-
tium may ultimately lead to a loss of tooth.
Though irreversible inammation may not
always result, if an irritating restoration is
present or a microbial infection ensues, it is
unlikely that healing will take place.1 Indeed,
it can signicantly reduce the odds of suc-
cess of root canal treatment by 56%, largely
attributable to bacterial contamination during
or after treatment.12 Several key factors have
been associated with the pathological seque-
lae and thus the prognosis of the tooth. These
include the site of the perforation, the size of
the perforation, the time to repair and, most
recently, the material with which the repair
is made (Table1).13
Site
The position of the perforation relative to
the level of the crestal bone and the epi-
thelial attachment is critical when assessing
prognosis. This is named the critical zone
(Fig.10). The worst prognosis lies when the
perforation is within this critical zone. The
close proximity to the gingival tissues can
lead to the contamination of the perfora-
tion with bacteria from the oral cavity.1 A
periodontal defect will be created if there
is apical migration of the epithelium into
the perforation site.14,15 This rapid pocket
formation leads to the lowest success rate
of repair.2,16 If the perforation occurs in the
furcation of multi-rooted teeth, then this can
also be regarded in the critical zone due to its
proximity to the epithelial attachment and
the gingival sulcus (Figs11a and 11b).8,17,18
Perforations that are coronal to the critical
zone have a good prognosis. This is because
they are easily accessible and an adequate
seal with conventional materials is possi-
ble without periodontal involvement. If the
canal is accessible and root canal treatment
possible, perforations that are located apical
to the critical zone also have a more favour-
able prognosis as they can be cleaned and
sealed with a much lower risk of bacterial
entry from the oral cavity and a chronic
inammatory lesion developing.18,19
Size
A small perforation is usually associated
with less tissue destruction and inamma-
tion. Therefore, healing is more predict-
able and has a better prognosis.20 Smaller
perforations are easier to seal effectively,
preventing bacteria from reaching the
peri-radicular tissues.1
Time
The time delay between the occurrence of
the perforation and repair has been found
to be an important factor in healing. The
most favourable healing is found when the
perforations are sealed immediately; thereby
reducing the likelihood of an infection and
chronic granulation tissue or periodontal
pocket occurring (Figs12a and 12b).8,14,21
Appropriate repair material
Historically, used repair materials are amal-
gam, zinc oxide – eugenol cement, calcium
hydroxide, gutta percha, glass-ionomer
cement, IRM, composite resin and SuperEBA
cement. Best practice suggests that perfora-
tions should now be treated using a bio-
active material such as mineral trioxide
aggregate (MTA (ProRoot, Dentsply/Tulsa
Dental, Tulsa, OK, USA)).22 This material
Fig. 10 The critical zone: a perforation
into the gingival sulcus and the crestal
attachment may have the most signicant
consequences as bacterial entry and
pocket formation can quickly ensue. It is
important to recognise the critical zone
may not necessarily be at the CEJ but rather
follows the biological width, thus if there is
recession, the critical zone will be located
more apically accordingly
Fig. 11 a) In an attempt to locate the disto-buccal canal of the 26, there were multiple
perforations of the pulp chamber oor. b) Upon re-entry the disto-buccal canal could not
be located but the perforation was repaired with MTA. There was radiographic evidence of
furcational bone loss. The tooth remained symptomatic and the tooth was removed
Fig. 12 In an attempt to locate the distobuccal canal of the 36 the operator perforated
into the furcation. The perforation was immediately repaired with MTA and the RCT
completed (to date) successfully
Table 1 The prognosis for success when considering site, size and time to repair of perforations
Prognosis Site Size Time to repair
Favourable Apical or supra-crestal Small Immediate
Unfavorable Equi-crestal Large Delayed
174 BRITISH DENTAL JOURNAL VOLUME 220 NO. 4 FEB 26 2016
© 2015 British Dental Association. All rights reserved
PRACTICE
consists of ne particles of tricalcium sili-
cates, which are hydrophilic and set in the
presence of moisture. It is biocompatible
and promotes tissue repair and regenera-
tion.23 Either under or over lling a per-
foration defect with MTA does not appear
to affect the ability to seal the root.24 With
most dental materials, the bond strength
signicantly reduces when it is contami-
nated with moisture, but MTA requires the
presence of water when setting. Therefore,
set MTA can acquire its optimal strength
and produce excellent sealability in the
inherently wet environment of the perfo-
ration.25 Once placed, MTA is biocompatible
and can result in new cementum forma-
tion and periodontal regeneration, despite
its extrusion into periradicular tissues.26,27
There are however, disadvantages of using
MTA:
• It is difcult to manipulate and handling
requires both time and practice
• The setting time of around fourhours
may compromise the application. In
supra-crestal cases the material may be
washed out before it has set28
• Both grey and white MTA can discolour
the tooth and therefore compromise
aesthetics. This needs to be considered
especially in the anterior region and with
those patients who have a high lip line.
Newer similar materials such as Biodentine
(Septodont) may overcome these handling
problems: it is a calcium silicate with cal-
cium chloride to speed the setting time.
As such it can be prepared, placed and set
within 12 minutes. (Figs13a-d) Furthermore,
it has improved handling ability with a con-
sistency closer to IRM or Kalzinol facilitat-
ing placement. As yet there is however a
paucity of data to support the use of such
materials.13,29,30
MANAGEMENT
The aim of perforation management is
regeneration of healthy periodontal tissues
against the perforation without persistent
inammation or loss of periodontal attach-
ment. If there is a case of periodontal break-
down, then the aim here is to re-establish
tissue attachment.26,31 Therefore, successful
perforation repair depends on the ability to
seal the perforation and re-establishing a
healthy periodontal ligament.8
Clearly, irrespective of site, size or time
to repair, if a tooth is symptomatic, treat-
ment must be offered. There are only two
options in this case: repair or extraction.
The tooth must rst be assessed for restor-
ability. Extensive pathological perforations
invariably render the tooth unrestorable.
If the tooth is unrestorable or endodontic
treatment deemed impossible to complete,
the patient must be counselled upon the
benets of extraction and possible pros-
thodontic options. For some teeth, access to
the perforation may be impossible without
signicant risk of collateral damage or risk
of failure, therefore, extraction may be the
only option (Figs14a and b).
If the tooth is considered restorable, repair
may be considered. An important factor to
consider is good visibility as this is essential
to see the damaged site. Access to an operat-
ing microscope is recommended.13
Non-surgical management of
perforations
General principles:
If possible, root canal treatment and deni-
tive obturation should be completed. If not,
the canals should be protected with an easily
removable material such as Cavit (3M ESPE,
Seefeld, Germany), cotton wool, gutta percha
or paper points. This prevents iatrogenic block-
age of the canals with the reparative material.
One must then consider the time-lapse
between the development of the perfora-
tion and the repair. If a non-contaminated
perforation is repaired immediately then
this prevents breakdown of the periodontal
ligament. If the perforation has been long
standing then it may be chronically infected.
Any restorative material within the perfora-
tion defect should be removed (Figs15a-c
and 16a-c). The success of treatment for
infected perforations depends on remov-
ing the contaminants and repairing under
aseptic conditions.32 If dentine must be
removed then this can be done with burs or
ultrasonic instruments under magnication.
Ultrasonic tips are the preferred choice as
they are least destructive to the adjacent tis-
sues. Arens & Torabinejad33 described further
enlargement and cleaning of the infected
Fig. 13 a–b) A perforation occurred
during endodontic access of the 45. c–d)
The cavity was repaired with Biodentine.
The setting time of 12 minutes allowed
the operator to continue RCT without
signicant delay to the patient’s care
Fig. 14 Following
extraction the size
of the perforation
is evident
BRITISH DENTAL JOURNAL VOLUME 220 NO. 4 FEB 26 2016 175
© 2015 British Dental Association. All rights reserved
PRACTICE
perforation and the wound site with copi-
ous irrigation of 2.5% sodium hypochlorite
before placement of the repair material.
Sodium hypochlorite should be used with
caution due to the increased risk of severe
complications. Sterile water can be used if
the operator is concerned about extrusion
into peri-radicular tissues, but they must be
aware this will not help decontaminate the
site. Chlorhexidine may be a preferable alter-
native if the patient is not sensitised to this.
When the lesions are larger they can
often present with hyperplastic and vascular
granulation tissue, which then protrudes into
the defect. This granulation tissue should be
carefully curetted and removed. Endodontic
excavators, probes and rose-head long shank
burs may also aid the clinician in achiev-
ing a clean cavity, but can result in further
profuse bleeding. Commonly used clotting
agents such as ferric sulphate can cause
irreversible damage to the delicate alveolar
bone and delay healing, as such their use
is not recommended.34-36 It is preferable to
achieve haemostasis using collagen, calcium
sulphate or calcium hydroxide. If bleeding
cannot be controlled it may be sensible to
dress the tooth and provisionally ll the
resorption defect with Cavit or non-setting
calcium hydroxide and arrange a further
appointment for the repair.
Controlling haemostasis and skillful
placement of a restorative material is essen-
tial in achieving a seal. In cases of delayed
repair there is invariably breakdown of the
periodontal ligament and surrounding bone
into which granulation tissue proliferates.
Removal of such granulation tissue may
therefore leave a bone cavity around the
perforation site.37 The operator must antici-
pate extrusion of repair material into this
cavity. In the past, attempts have been made
to control this and to increase the sealing
ability of the repair materials with internal
biocompatible barriers/matrices such as
collagen or calcium sulphate (Fig.17).38-41
However, there is some evidence to sug-
gest that an excellent success rate is achiev-
able when MTA is used without a barrier.20
Furthermore, when MTA was accidently
extruded into the periradicular area, it was
shown that hard tissue was deposited over
the material with the presence of a healthy
periodontium. All this conrms that MTA
works favourably when it is extruded into
the periradicular tissues. Thus, the use of
barriers is not strictly necessary with cal-
cium silicates such as MTA. If, however,
there is a large cavity it may be worth
considering placing a barrier to facilitate
control of the material. Propriety cellu-
lose materials used in surgical haemostasis
control are inexpensive, easy to manipulate
and ideal for this. Once placed, the MTA
or other such material can be condensed
against the barrier permitting improved
control of the repair.
Fig. 16 a –b) The treating practitioner perforated through the mid buccal of of the 12. The
root canal treatment was completed but the referring practitioner was completely unaware
they were obturating the periodontal tissues. c) Orthograde root canal treatment was
completed and the perforation repaired with composite as the defect was supra gingigval. The
site was surgically explored to remove extruded GP. Note the signicant bone loss around the
apex of the 12
Fig. 15 Careless access with no consideration
to the position of the root resulted in a distal
perforation of the 12 distally. Furthermore an
instrument separated during preparation. This was
removed before conventional RCT and perforation
repair was undertaken
176 BRITISH DENTAL JOURNAL VOLUME 220 NO. 4 FEB 26 2016
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PRACTICE
Coronal third perforations:
The location of the perforation will deter-
mine which access technique is used and
how the perforation is sealed. Supracrestal
perforations have no periodontal involve-
ment as they communicate directly with the
oral environment. Conventional restorative
materials such as glass ionomer and compos-
ite may be used but care should be taken to
ensure the margins of the repair are smooth
externally and do not become a plaque-trap.
If feasible, MTA or equivalents should be
used for those lesions in and just apical to
the critical zone. The root canal treatment
may be completed and the repair performed
or, if the perforation is bleeding and impair-
ing RCT, it may be sensible to repair the per-
foration before completing RCT (Fig.18).
MTA can be delivered to the perforation
using micro-syringes such as the MTA MAPS
System or Dogvan Carrier. Micro pluggers or
micro spatulas can then be used to condense
the material. Though ultrasonic instruments
can be used to help ‘slump’ the material into
the site and improve adaptation, it is in the
authors’ belief that this can irritate the tis-
sues and result in unwanted bleeding.13
Once MTA is placed precisely, a paper point
or cotton pledget can be used to remove the
excess moisture, which further solidies the
material.42 After placement is complete, a damp
cotton pledget is placed on top allowing MTA
to set, as it needs more moisture during setting.
This protracted setting time dictates a delay
in the placement of the nal restoration. The
recommendations vary from one day to one
week.33 Sluyk et al.43 showed that at a time
range of 72h, the resistance to dislodgement
improves signicantly. During the next visit,
it is recommended to check if the material is
set and whether it has remained correctly posi-
tioned at the perforation site. Immediate adhe-
sive reconstruction of the tooth provides less
possibility for coronal leakage and strengthens
the tooth. In the authors’ opinion, when MTA
is used it is not unreasonable to place a bar-
rier of resin modied GIC over the MTA and
restore the tooth immediately. If Biodentine is
used, the restoration may be placed immedi-
ately onto the repair. Indeed it may be sensible
to initially restore the whole tooth completely
with Biodentine (Figs19a and 19b).
Middle third perforations:
These are usually ovoid in shape and typi-
cally consist of a large surface area to seal.32
Strip perforations are frequent problems
in thin and concave roots.44 These defects
are almost impossible to repair in a truly
controlled manner (Fig.17). If only a small
defect is suspected, and haemostasis is
achieved immediately, it may be sensible
to obturate conventionally. If the defect is
canal from obstruction with the repair
material. This must be placed deeper
than the perforation. Different space-
maintainers have been recommended
including severed les,42 but a GP cone
or paper points are readily available,
inexpensive and easy to remove once
the repair is complete.
These operators feel it is invariably
easier to obturate the canal apical to the
defect, repair the defect then backll the
canal around the repair with warm ow-
able gutta percha, but this is clearly per-
sonal preference and clinical flexibility
is essential.
larger this may prevent adequate healing
and some attempt must be made to repair it.
It is necessary to be vigilant in placing the
instruments in the original canal and not
the perforation. This is facilitated by pre-
bending root canal instruments and ling
away from the defect.
There are two options for repairing these
perforations:
1. Sealing the defect with MTA after
obturating the canal apical to the
perforation. The gutta percha can be
heated and placed against the canal
wall opposing the perforation. This
eases the application of MTA to the
perforation, which is placed at the level
of the defect and condensed by hand.
The disadvantage that comes with this
technique is the risk of extruding the
obturation material into the perforation
2. Clean and shape the canals then, after
hemostasis has been achieved, use
a ‘space-maintainer’ to protect the
Fig. 18 The root canal treatment of the 21
and 11 (from Figure 9) was completed and
the buccal perforation to the 21 was repaired
with MTA
Fig. 19 Once the bleeding in Figure 7 was controlled (using adrenalin containing local
anaesthetic injected interproximally and gentle pressure with cotton wool pledgets) the
perforation was repaired with Biodentine. Again, this permitted the clinician to continue
endodontic therapy during that visit
Fig. 17 During the repair of the perforation
in Figure 2, MTA was extruded into the
peri radicular tissues. Arguably, though
challenging to place, a barrier may have
prevented this
BRITISH DENTAL JOURNAL VOLUME 220 NO. 4 FEB 26 2016 177
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PRACTICE
Apical third perforations
These perforations can be difcult to man-
age. They often occur during cleaning and
shaping of the root canal.32 Access is invari-
ably limited and negotiating these frequently
blocked and ledged canals is difcult. Using
MTA to restore these defects may be impos-
sible unless it is a straight wide canal and the
operator can sufciently visualise the lesion
(Figs20a-c). We advocate attempting to re-
access the original anatomy and, following
cleaning and shaping, obturation with warm
vertical compaction of gutta percha, relying
upon the sealer and some GP to ow into the
defect. If re-access is not possible then obtu-
ration to the defect may be carried out, with
warm vertical compaction of gutta percha. It
must be noted, however, that apical perfora-
tions with uninstrumented canals may face
a much poor prognosis and cannot be man-
aged successfully in all cases. Consideration
should be given to the options of apical
surgery or extraction, should pathology and
symptoms persist.42
Surgical management of
perforations
In the past, before technology such as
magnication and illumination became
readily available, perforations were often
managed surgically. With these advances,
it is now considered appropriate to use a
non-surgical approach whenever possible.13
However, surgical intervention may be
considered when:
• There is uncertainty about the shape/
nature of the defect
• The defect is sub-crestal and associated
with pathology and/or symptoms
• Internal access is not possible because of
an extensive intracoronal/extra coronal
restoration
• There is a large defect preventing control
over materials
• There is an apical third perforation
with persistent disease that cannot be
adequately cleaned and repaired
• There is external cervical resorption not
amenable to internal repair
Essentially, surgical management is indi-
cated if either the case is not amenable or
not responding to non-surgical treatment,
or if management of the affected periodon-
tium is required.13,45 Root canal treatment
should be completed. A surgical ap is then
reected at the perforation site to provide
access for surgical repair. In instances when
the defect is in the coronal half of the tooth
it is prudent to lift a full mucoperiosteal ap.
It provides good access and can be a rec-
tangular ap with mesial and distal vertical
relieving incisions, triangular with just one
or, if the ap can be mobilised sufciently,
it may be possible to access the lesion with-
out a relieving incision (Figs21a-d). In cases
where the lesion is located more apically it
Fig. 20 a) Whilst attempting to locate the canal of the 22 the operator perforated the distal aspect of the apical third. b) The canal was
correctly identied and shaped. Following this GP was used to obturate the apical canal before MTA was placed over the perforation.
c) The canal was backlled with warm owable GP
Fig. 21 a) A perforation occurred during RCT of the 12 resulting in a persistent sinus. b–c) An intra-sulcular incison was made and a ap
raised without relieving incisions. Surgical repair with MTA was performed. d) There was evidence of healing and no pocketing at a 4 week
review
178 BRITISH DENTAL JOURNAL VOLUME 220 NO. 4 FEB 26 2016
© 2015 British Dental Association. All rights reserved
PRACTICE
may be sensible to use papilla base preserva-
tion techniques or sub marginal incisions.
Preparation of the perforation site may be
performed with a piezo-electric ultrasonic
hand piece or a small round bur can be used,
but often, simple hand instrumentation with
curettes will sufce. Haemostasis should then
be achieved before the restorative material is
placed in the perforation defect. As described
above, a biologically compatible material
should be thoroughly compacted into the cav-
ity to ensure a dense ll. If haemostasis cannot
be achieved the operator must make a deci-
sion about how to proceed. MTA type materials
‘wash out’ in wet environments and it may
not be possible to manipulate them adequately.
Resin bonded materials require immaculate
moisture control. The fall back option remains
resin-modied glass-ionomer cement. Though
this material is also moisture sensitive its han-
dling properties, setting time and self-adhesive
nature permit a compromised repair in dif-
cult circumstances. If there is a bony cavity it
should then be carefully debrided and all the
debris is removed before the ap is replaced
(Figs22a and 22b).45
It is reported that success rates may vary
between 30% and 80% which further reiter-
ates the fact that non-surgical repair should
always be carried out whenever possible.46,47
CONCLUSION
Perforations can result in chronic infection
and ultimately tooth loss. Prevention of
iatrogenic damage is an essential part of
all healthcare interventions. Table2 con-
tains some tips on good preventive strate-
gies. Nonetheless, perforations can and do
occur for a variety of reasons. It is essential
the clinician recognises when a perforation
has occurred and has knowledge of the best
strategy for correcting the damage. A refer-
ral to a more experienced colleague may
result in a delay in treatment, which may
have serious impact upon the outcome of
treatment, therefore, all clinicians should
consider immediate repair with the appro-
priate materials. Patients must be informed
that long standing perforations may be
unpredictable to repair and consent must
include the risks and benets of either leav-
ing the tooth unrepaired or extraction and
prosthetic replacement.
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Use magnication and good illumination when providing endodontic treatment.48
Remove impediments to straight-line access: this reduces the cur vature of the canal.
Begin a crown down approach before apical instrumentation. This facilitates instrumentation, prevents
instruments locking in the canal and allows improved irrigation.
Negotiate canals initially with size 10 ISO les and progress to size 20 ISO les before introducing rotary
instruments.
Use ‘ne les frequently’ between larger les to prevent blockages and ledging.
Use copious irrigation with 1%-5.25% sodium hypochlorite to remove debris.
In curved canals use balanced force technique for hand ling.
Always follow manufacturer guidelines on rotary instrument protocols.
Never force a le.
If you suspect a blockage or ledge, do not use rotary instruments.
In teeth with multiple roots always le away from the furcation with brush strokes of the instruments.
If there is any doubt about access, working length or possible perforation, take a check radiograph.
Fig. 23 Key concepts to avoid perforation during endodontic treatment
BRITISH DENTAL JOURNAL VOLUME 220 NO. 4 FEB 26 2016 179
© 2015 British Dental Association. All rights reserved
PRACTICE
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© 2015 British Dental Association. All rights reserved
