Quality Resource Guide
l
Managing Endodontic Treatment Failures 2nd Edition
2
www.metdental.com
Endodontic treatment failures typically demonstrate
complexities (root morphology, tooth position,
comorbidities) and should generally be treated
by a general practice dentist with extensive
experience in endodontic therapy, or referred to
an endodontist, to assure optimal results from
retreatment. This Quality Resource Guide (QRG)
summarizes important aspects to help the general
dentist to identify endodontic treatment failures,
determine potential causes of the failure, and
assist the patient to determine appropriate steps to
address the failure. The QRG will also briefly review
contemporary endodontic approaches that may
be used in retreatment of endodontic failures, so
the practitioner may better discuss those potential
options with the patient and other clinicians who
may become involved in therapy.
Diagnosis of an Endodontic
Treatment Failure
The initial consultation with a patient demonstrating
a history and symptoms consistent with a tooth
experiencing endodontic failure should allow
adequate time to listen to the patient’s chief
complaint, and any additional information they may
possess (length of time since the previous treatment,
why the treatment was performed, any issues that
occurred during therapy or during the post-operative
period, and past, as well as current symptoms).
Information obtained from the clinician providing
initial therapy, as well as any other clinicians the
patient has seen to address the present symptoms
may add helpful details.
Proper diagnostic procedures, including clinical and
radiographic examinations (
Table 1
) must be carried
out. Ideally, conventional periapical radiographs
should be taken from different angulations and, in
some cases additional images obtained from cone
beam computed tomography (CBCT) may be of
assistance (
Case 1
).
The clinician should consider these aspects following
obtainment of clinical and radiological data:
• Positive palpation and percussion are generally
indicators of apical periodontitis or inflammation
of the periodontium.
•
Occlusal evaluation and adjustment, if necessary,
should be completed to eliminate occlusal
stresses as a potential factor for symptoms.
Introduction
Preservation of a patient’s natural dentition remains
an important aspect in securing his/her oral health.
Conventional endodontic therapy has been shown
to be a very predictable treatment modality (success
approximately 90%) for infected pulpal tissue.
1
However, endodontic therapy can occasionally fail.
2
Signs and symptoms of endodontic treatment failure
include radiographic apical/periapical radiolucency,
swelling,
sinus
tract
and
pain.
Treatment
inadequacies are the major cause of endodontic
failure.
3-5
The most common treatment deficiencies
leading to failure include:
•
Inappropriate or inadequate debridement of
microorganisms and their products from the root
canal system, especially in anatomically complex
or missed canals.
•
Iatrogenic
complications,
such
as
root
perforations, ledges, over or under extension of
the root canal filling, and separated instruments.
•
Inadequate fill and/or seal, resulting in coronal
leakage and/or leakage around the canal filling
material.
•
Inability to adequately remove apical calculus or
extraradicular biofilms.
•
Failure to detect tooth fracture
Infrequently, endodontic treatment may appear to
have followed the highest practice standards and
yet may fail. Failure is most often attributed to a
persistent or secondary intraradicular infection in
these situations, although extraradicular infections
cannot be discarded as a potential cause.
3
An important step in evaluating a tooth with
failed endodontic therapy is assessing why the
previous endodontic treatment may have failed and
determining what additional care is best suited
for the patient. Treatment options to save natural
teeth should generally be very carefully considered
before recommending extraction of a tooth with
failing endodontic therapy. An endodontically treated
tooth that has clinical symptoms and/or persistent
apical periodontitis will often respond to nonsurgical
endodontic retreatment, apical surgery, or intentional
replantation.
6
•
The presence of a positive response to thermal
and electric pulp tests in a tooth having previous
endodontic treatment may be an indication of
missed or untreated canals.
•
Sinus tract/parulis must be traced with a gutta-
percha cone to localize the source of infection.
• A tooth with a deep periodontal pocket in a
localized region may indicate root fracture.
•
Periodontal attachment loss and tooth restorability
should be carefully evaluated when considering
endodontic retreatment, apical surgery or
intentional replantation.
• Coronal microleakage through inadequate or
fractured coronal restorations, as well dental
caries, are common causes of treatment failure.
•
Apical radiolucency alone is not an indication for
endodontic retreatment.
• Additional signs and symptoms, as well as
information provided by the patient and treating
dentists, must be carefully considered before
considering retreatment procedures.
Table 1
- Diagnostic Assessment
Clinical Examination Procedures
Palpation
Percussion
Thermal tests
Electric pulp test
Periodontal probing
Tooth mobility testing
Transillumination and staining
Assess signs of inflammation, redness,
swelling, fistula/parulis
Radiographic Evaluation Questions
Dental caries?
Calcification(s)?
Radiolucencies or radiopacities?
Root resorption?
Root perforation(s) and/or fracture(s)?
Quality of root canal filling or altered canal
anatomy?
Intracanal post(s)?
Previous apical surgery?