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.
Whilst taking the dental history, the clinician should
be formulating a provisional diagnosis in his/her mind.
The provisional diagnosis should be based on the
patient’s chief complaint, their description of the
symptoms and a thorough history of any relevant
problems and any prior dental treatment (Table 3). The
provisional diagnosis should be made prior to
examining the patient and his/her mouth and teeth. The
subsequent clinical and radiographic examinations
together with the appropriate clinical tests are used to
confirm (or change) the provisional diagnosis. Extra-oral,
intra-oral soft tissue and dentition examinations
should be performed to establish the patient’s overall
oral health. Clinical tests include pulp sensibility tests
and peri-radicular tests (e.g., percussion, palpation,
mobility) that are aimed to reproduce the patient’s
symptoms. Some periradicular tests (e.g., periodontal
probing, mobility) also help to assess the integrity of
the attachment apparatus of the tooth and the extent of
inflammation of the periodontal ligament resulting
from periodontal disease and pulp inflammation. Pulp
sensibility tests measure the ability of the pulp’s nerve
fibres to respond to a stimulus. Among the tests
available clinically, the cold pulp sensibility test is the
most useful test and the dry ice (carbon dioxide) test is
the most reliable and reproducible of the various cold
tests available commercially.
“Cold sprays” and ice
have been shown to be only about 40–60 per cent
accurate; therefore they should be considered as
unreliable
and hence they are not recommended for
use. Severe and prolonged response to a cold stimulus
is indicative of irreversible pulpitis, whereas no
response could indicate pulp necrosis, a pulp confined
in an obliterated canal, a previous pulpotomy or a
previously filled root canal. Heat tests are not used
routinely unless the major symptom reported by the
patient is sensitivity to a hot stimulus. An exaggerated
and lingering response to heat testing is indicative of
irreversible pulpitis. Electric pulp tests can give false
negative results (e.g., in some obliterated canals) or
false positive results (e.g., with pus in canals, necro-biosis or
improper technique). Hence electric pulp
sensibility tests are only useful in some cases of coronal
pulp canal calcification when cold tests are
inconclusive, or as an adjunct during the follow-up of
trauma to the teeth. When selecting the appropriate
clinical test, one has to remember that no single test is
sufficient to make a firm diagnosis of reversible or
irreversible pulpitis and therefore multiple tests are
required. Periodontal examination of the suspect teeth
is essential in all cases because periodontal diseases can
mimic endodontic problems and they are often inter-related.
Periodontal probing depths also help to
determine the prognosis of the tooth. Transillumination
of the tooth is a particularly useful examination
procedure that can be used to readily detect cracks in
teeth (Fig 2),
routine examination of all teeth with pulp or periapical
diseases, especially following trauma (Table 4).
In the above discussion, the term “pulp sensibility
test” has been used. It should be noted by clinicians
that the older, and sometimes more commonly used
term “vitality tests” is no longer recognized as being
appropriate since thermal and electric tests do not test
the “vitality” of the tooth or the pulp. The term
“vitality” refers to the presence of blood supply to the
tissues whereas the term “sensibility” is defined as the
ability to respond to a stimulus. Hence, “sensibility” is
the appropriate term to use since thermal and electric
tests are assessing whether the nerve fibres within the
pulp are able to respond to the hot, cold or electrical
stimulus. If the pulp’s nerve fibres do respond, then an
assumption is made that there must be a viable blood
supply to keep the nerve fibres alive and functioning,
and therefore the rest of the pulp tissues and cells are
probably also alive and functioning. However, these
tests do not necessarily indicate the degree of health or
disease within the pulp. It is also important to
remember that the nerve fibres are usually the last part
of the pulp to undergo necrosis, especially in the apical
part of the canal, and therefore a “false positive”
response may be obtained from a pulp that is essentially
necrotic.
The main functions of pulp sensibility tests are to,
firstly, determine whether there is a nerve response and,
secondly, to assess the nature of the response. If there is
a response, then the pulp may be alive, whereas no
response may indicate necrosis, pulp canal calcification,
or a tooth that has had a pulpotomy or a root canal
filling, as discussed above. This is important when the
provisional diagnosis was pulp necrosis or a pulpless
canal as here the clinician is searching for the tooth that
does not respond. However, if the provisional diagnosis
was pulpitis (either reversible or irreversible), then the
clinician is searching for the tooth that has an
exaggerated response which replicates the pain
experienced by the patient – that is, the degree of
sensitivity of the pulp (note: sensitivity is defined as an
exaggerated response and is different to sensibility).
The severity can also help to distinguish between
reversible and irreversible pulpitis but the time that the
pain lingers after removing the stimulus is usually of
more value to distinguish between these two
conditions. In this latter scenario of testing for pulpitis,
the pulp sensibility tests could be considered as
“sensitivity tests” as they are assessing which tooth
responds more severely than the others.
Pulp sensibility tests cannot be interpreted without
also viewing an accurate and current periapical
radiograph of the tooth in question. The results of pulp
sensibility tests should correlate with the radiographic
appearance of the tooth and the periapical tissues
before making a definitive diagnosis. As an example, a
tooth that does not respond to a pulp sensibility test
could have a necrotic pulp (with or without infection),
a pulpless, infected root canal system, or pulp canal
calcification. It may also have had a root canal filling,
a pulpotomy or a partial pulpectomy, all of which may
or may not be infected. All of these conditions can only
be fully assessed by viewing a periapical radiograph
and therefore the pulp test result could be misinter-preted
if a radiograph is not viewed. The radiograph
also needs to be a current radiograph since pulp and
periapical diseases are progressive in nature and will
change over time. Hence, an accurate diagnosis of the
current condition cannot be based on a radiograph
taken several weeks, months or years earlier, and some
times even one taken just several days earlier.
Radiography may arguably be the most reliable of all
the diagnostic tests although it may not help in the
assessment of teeth with pulpitis. However, radiographs
will always provide valuable information to assist with
diagnosis and treatment.
A routine radiograph may sometimes be the first indication of the presence of
pathosis, such as internal root resorption or chronic
apical periodontitis. The cause of the pulp disease (deep
caries, deep restorations, open margins, etc.) may also
be evident on radiographs. A widened periodontal
ligament space or a periapical radiolucency that cannot
be “moved” with tube-shift radiography may be
diagnostic for periapical pathosis. However, radio-graphy is
not a perfect diagnostic tool. Soft tissue
diseases of the pulp are not visible on radiographs; only
hard tissue changes can be seen on radiographs.
Radiographs only provide a two-dimensional
representation of three-dimensional structures.
Periapical lesions may not be directly evident on the
radiographs and their real extent and the spatial
relationships to anatomical structures may not be
readily visualized. Periapical lesions also take some
time (2–10 months) to develop to a size which will be
evident on a radiograph.
A pretreatment diagnosis is made after interpretation
of all the collected information. This diagnosis should
include an assessment of the pulp or root canal
condition, the periapical status and the cause of the
disease(s).
Ideally, there should be at least two
different signs and/or symptoms present to indicate and
confirm the disease(s).
Only at this stage can the management of the patient’s problem(s) be planned.
It is not possible to diagnose the histological status of
the pulp from the clinical signs and symptoms.
Diagnosis of the level of pulp inflammation is difficult
but it is relatively easy to determine from clinical findings
that a pulp is necrotic or the canal is pulpless. Severity
and duration of pain appears to be related to the status
of the pulp. Severe lingering pulp pain usually indicates
the presence of acute irreversible pulpitis with an
increase in pulp tissue pressure. When mild to moderate
pain of very short duration is present with no previous
history of pain in the tooth, reversible pulpitis may be
occurring. If the tooth is associated with a previous
history of pain, irreversible pulpitis is more likely.
Sometimes the clinical and radiographic examinations
are inconclusive yet the patient has pain. However, it is
important not to initiate irreversible treatment without
a definite diagnosis. In these cases, the correct
procedure is to make a provisional diagnosis. Referral
to an appropriate specialist should be considered in
such cases, although if not feasible then, guided mainly
by the radiographic findings, such as the deepest
restoration in the suspect quadrant or caries close to the
pulp, the likely tooth can be identified and treated with
zinc oxide-eugenol cement that has an excellent local
anaesthetic and sedative effect. If necessary, one tooth
at a time is treated this way until a definitive diagnosis
is established. It is most likely that only one tooth is
responsible for acute pain. However, if there is very
little evidence that provides definitive information, then
either specialist referral or a conservative “wait and
see” approach may be necessary in order to allow the
vague symptoms to localize to the specific tooth. It is
important to understand, and remember, that pulp and
periapical diseases are progressive and therefore the
symptoms will vary over time, which usually assists the
localization and the diagnosis of pain.
Complete patient care must include a discussion of
the diagnosis with the patient. It is essential to disclose
the examination findings and for the patient to under-stand
his/her presenting condition(s). Details of the
recommended treatment, the prognosis and the
alternatives to treatment should be discussed as well as
the consequences if no treatment is performed.