Considerations in Endodontic Diagnosis
Endodontic diagnosis can often be complex. Findings may not always be consistent, and
the process of arriving at a diagnosis depends on our critical
interpretation of the findings.
We have to rely on the patient’s subjective data reporting
that is often clouded with multiple complaints and can present
the following scenarios:
ASSUME THAT PULPAL PROBLEMS CAN BE SEEN ON A RADIOGRAPH
Radiographs present the least accurate
data for diagnosing irreversible pulpitis. If the pulp is still vital and there is no percussion sensitivity
then there is no apical extent of inflammation. Even in the presence of osteolytic
inflammation, 50% of one of the bone cortices must be resorbed
to observe a lesion on the radiograph. The radiograph can, however,
provide clues to pulpal problems by observing caries and restorations.
In this respect, a bite-wing radiograph is an excellent endodontic
TOOTH DOESN’T HURT ANYMORE WHY DO I NEED A ROOT CANAL?
Patients often experience the intense pain of irreversible
pulpitis that then diminishes by the time they seek treatment
or are referred to a specialist. The most reliable test for the apical extent
of pulpal inflammation is the simplest – percussion. The pulp
has no proprioceptive nerve fibers but bone does.
Once inflammation escapes apically, the specific tooth
will be identifiable. Pulp testing with a thermal agent such as
carbon dioxide snow (dry ice) is an important part of diagnosing
non-vital pulp and assuring the patient that they need endodontic
treatment before the necrotic tissue causes an infection.
Having the patient observe testing in a mirror is great
for providing feedback and education. Explain that they are no longer having pulpal
pain because the pain conducting fibers have been destroyed but
they have “traded” that pain for the pain of bone inflammation. Once again, in the early stages of this process
a lesion may not be present radiographically.
I HAD A ROOT CANAL BUT
IT STILL HURTS WHEN I DRINK COLD THINGS
This is one of the most common and confusing complaints
and definitely requires patient convincing and education.
Over 90% of all pulpal nociceptive fibers terminate in
the coronal pulp and pulp horn areas. Even incomplete endodontic
treatment e.g. partial pulpotomy or pulpectomy will render the
tooth completely insensible to cold. Even if a canal was missed during previous
endodontic treatment, there will be insufficient tissue present
to react to a cold stimulus.
Generally, the patient is implicating a adjacent tooth
that probably has cervical dentin exposure, most likely from toothbrush
abrasion. Remember, tooth
structure is not conductive to temperature at the same rate that
the patient perceives a temperature change. The pulp perceives
temperature change simply by the movement of tissue fluid within
the dentinal tubules in the presence of intact a-delta pain fibers
that line the pulp chamber. Any stimulus that causes fluid movement
causes pain. Research has proven that a temperature stimulus has
to be placed on tooth structure (in a constant state) for approximately
a minute in order to measure a temperature differential on the
pulpal side of the tooth structure. Patients don’t stimulate their
teeth with hot or cold foods and liquids for that constant period
water ice to reproduce a chief complaint of cold sensitivity but
use carbon dioxide snow or Endo Ice spray to test for intact nerves.
sensitive teeth do not have apical lesions. Conversely, endodontically
treated teeth cannot be temperature sensitive.
Teeth with large apical lesions cannot be temperature sensitive.
ENDODONTICS 488 EAST VALLEY PARKWAY SUITE 307 ESCONDIDO, CA 92025
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