Pulp vitality test is crucial in monitoring the state of health of dental pulp,
especially after traumatic injuries. The traditional pulp testing methods such
as thermal and electric pulp testing methods depend on the innervation and
often yield false positive and negative response. The newer pulp testing
devices, some of which are still under development stage, detect the blood
supply of the pulp, through light absorption and reflection, are considered
to be more accurate and non-invasive. The article attempts to discuss issues
related to pulp vitality testing in clinical endodontic practice and describes
the principle on which these newer pulp testing devices are based and its
mode of working.
The assessment of pulp vitality is a crucial
diagnostic procedure in the practice of
dentistry1. Current routine methods rely on
stimulation of Ad nerve fibers and give no direct
indication of blood flow within the pulp. These
include thermal stimulation, electrical or direct
dentine stimulation. These testing methods
have the potential to produce an unpleasant
and occasionally painful sensation and
inaccurate results (false positive or negative
can be obtained in many instances). In addition,
each is a subjective test that depends on the
patient’s perceived response to a stimulus as
well as the dentist’s interpretation of that
response2. Recent studies have shown that
blood circulation and not innervation is the most
accurate determinant in assessing pulp
vitality3,4 as it provides an objective
differentiation between necrotic and vital pulp
tissue. This article highlights tests relying on
the passage of light through the tooth to detect
pulp vitality with greater objectivity. They rely
either on the detection of changes in the light
absorption as it passed through the tooth, as
in photoplethysmography, pulse oximetry and
dual wavelength spectrophotometry5 or the
shift in light frequency as it is reflected back
from a tooth, as in laser Doppler flowmetry6.
This paper attempts to review the newer pulp
vitality testing methods.