This document discusses various methods for diagnosing dental caries. It describes the ideal requirements of a caries diagnostic test, such as being accurate, sensitive, specific, reliable and reproducible. It then examines numerous in vivo and in vitro methods for caries diagnosis, including visual examination, radiographs, fiber-optic transillumination, fluorescence techniques, and more novel methods like magnetic resonance microimaging and optical coherence tomography. Each method is described in terms of its principles, advantages, limitations and appropriate uses in diagnosing dental caries.
2. Caries diagnosis is the art or act of
identifying a disease from its signs and
symptoms.
3. IDEAL REQUIREMENTS OF A CARIES
DIAGNOSTIC TEST:
The use of appropriate diagnostic methods
must be made according to the situation, for
example,
Use in clinical situations
Laboratory studies or research work
Community studies.
4. An ideal caries diagnostic test must be
• Accurate
• Sensitive
• Specific
• Reliable
• Reproducible
• Should not transfer S.mutans
or other bacteria from affected
area to unaffected areas
• Cost effective
10. VISUAL EXAMINATION:
The visual examination of caries
encompasses the use of criteria such as
detection of white spot , discoloration
and frank cavitation.
11. EKSTRAND criteria for presence or
absence of occlusal caries-
V0- No/slight change in enamel
translucency after prolonged air drying
(more than 5 sec)
V1- Opacity/ discoloration hardly visible
on wet surface, but distinctly visible after
air drying
V2- Opacity/ discoloration distinctly
visible without air drying
12. V3- Local enamel breakdown in opaque or
discolored enamel and / or grayish
discoloration from underlying dentin
V4- Cavitation in opaque/ discolored
enamel exposing dentine.
13. Aids in the visual diagnosis of caries:
1. A magnification loupe
2. Temporary elective tooth separation
14. • A major shortcoming is that this
method is very limited for detecting non
cavitated lesions in dentin on the
posterior approximal and occlusal
surfaces.
15. Meticulous clinical visual method:
Meticulous clinical examination
following cleaning (including flossing) of
all surfaces and thorough drying will
disclose more lesions than the other
methods.
16. Visual method with temporary elective
tooth separation:
This method permits a more
definite assessment of whether
radiographically detectable approximal
enamel and dentin lesions are cavitated
(Pitts & Rimmer 1992).
17. Visual method with temporary elective
tooth separation and impression of the
approximal lesions:
Temporary elective tooth separation,
complemented by a localized impression of
the opened interproximal space, allows a
more sensitive diagnosis of cavitation than
does the purely visual separation method.
18. This also has the advantage of providing
a replica as a reference for visual
monitoring of changes in size or even
measurement of serial measurements.
(Neilson&Pitts1933, Seddon1989).
19. TACTILE EXAMINATION:
Explorer and floss .
The explorer can be of different varieties
such as:
•Right angle probe (NO 6)
•Back action probe (NO 17)
•Shepherd’s crook (NO 23)
•Cow horn with curved ends (NO 2)
20. Use of explorers:
An explorer is useful in caries diagnosis as
a tool to remove plaque and debris and
check the surface characteristics of
suspected carious lesions.
There is no need to apply too much
pressure on an explorer because studies
have found that this does not increase the
accuracy of caries detection (Lussi 1991).
21. The use of gentle pressure, defined by the
force just required to blanch a fingernail
without causing any pain or damage, is
highly recommended.
22. All surfaces of a tooth are cleaned of
debris and plaque, the teeth are dried
using an air syringe and examined
visually. If there are suspicious areas,
then an explorer is used to check for the
surface texture.
23. The use of explorer condemned because :
•Sharp probe tips can cause physical
damage to small lesions with intact
surfaces.
•Probing may lead to fracture and
cavitation in the incipient lesion.
•Normal dental examination with an
explorer may spread the organism in the
mouth.
24. Caries is diagnosed if the tooth meets the
ADA criteria of softened enamel that
catches an explorer and resists its removal
(the so called sticky fissure ) or allows the
explorer to penetrate proximal surfaces
under moderate-to-firm probing pressure
(Green Verdman Black,1924).
25. •Mechanical binding of the explorer in the
fissure may be due to non-carious reasons,
leading to the feeling of catch.
•The stickiness of fissure may depend on
factors such as:
• Shape of the fissure
• Sharpness of the explorer
• Force of application
• Path of explorer placement
• Withdrawl of the explorer&
• Width of the explorer tip.
26. Use of floss as an adjunct to tactile
sensation:
PICKARD (1961) has suggested the use of
floss for detection of caries.
Fraying of a piece of dental floss, when it is
passed through an apparently normal
contact area points out that the area is the
site of early carious detection.
27. RADIOGRAPHS:
Since the carious process results in
demineralization, the affected area of the
tooth becomes more radiolucent (or less
radio dense) than the unaffected portions
of the tooth.
28. The carious area attenuates less
radiation than the intact tooth surface so
that the film in the area of its image
receives a higher exposure and then is
darker on the processed radiograph.
29. Conventional:
Conventional radiographs (bitewing &
IOPA) are most frequently used for the
detection of caries.
Conventional bitewing radiographic
method:
It discloses sites inaccessible to other
methods.
It facilitates detection of carious lesions at
an earlier, potentially reversible stage.
Depth of the lesion can be evaluated and
scored
30. Eg: Radiographic index by Grondahl et al
(1977) modified from Moller &
Poulsen(1973):
0 – no radiographic changes in enamel
1 – radiographic changes in enamel
2 – radiolucency extending to the DEJ
3 – radiolucency penetrating
approximately halfway through dentin
4 – radiolucency close to the pulp.
31. Radiograph provides
• A permanent record
• Recall examination-assessment of
progression or regression of lesions
• Evaluation of disease activity
• Efficacy of preventive and therapeutic
measures
• Noninvasive.
32. Limitations:
•2-D image of an object.
•Standardized geometric angulation,
exposure time, processing procedures and
analyzing facilities are necessary.
• Does not disclose the earliest stages of
lesion development. 30-40% mineral loss
33. •Underestimate the extent of
demineralization.
•Approximal secondary caries on the
more apical part of a restoration may not
be detected.
•Noncavitated carious lesions on the root
are difficult to diagnose.
34. Advances:
•Digital radiography either with charge
couple device technology or storage
phosphor screen technology has been
used.
Advantages such as:
• less image resolution
• less radiation required
• the image detector is generally larger
35. • the image is immediately available
• image can be electronically transferred
• image may be enhanced.
36. XERORADIOGRAPHY
It is a technique that uses the xerographic
copying process to record images produced
by diagnostic X-rays. This technique does
not make use of the wet processing of the
image receptor.
In xeroradiography, the image formation
is achieved by a photo electrostatic
process and not by photochemical process.
37. Advantages:
• Less radiation and edge enhancement.
• Wide latitude of exposure.
• Used in the diagnosis of dental caries.
38. FOTI has been used in common medical
procedures since 1960.
In 1970, Friedman & Marcus suggested
the use of FOTI in detection of carious
lesions.
39. Principle:
The principle of transillumination is that
there is a different index of light
transmission for decayed and sound tooth.
Since tooth decay has a lower index of
light transmission than the sound tooth
structure, an area of decay shows up a
darkened shadow that follows the decay
along the path of dentinal tubules.
40. USES:
• Effective, specially when
used in the anterior region
as usage in the
posterior region is
associated with some
difficulty.
• Advocated as an adjunct to visual and
radiographic methods.
41. • useful for caries detection anywhere in
the mouth where proximal decay is
adjacent to a radiopaque restoration, or
a tooth containing a radiopaque occlusal
restoration.
• Can be used along with dyes for the
enhancement of visualization.
42. The advantage of the methods:
Simple
Comfortable for the patient
Noninvasive
The limitations of the method:
Only used for approximal surfaces
Secondary caries cannot be diagnosed.
44. DIGITALLY IMAGED FOTI:
It is a recent innovation to fiber optic
transillumination introduced by Electro
optical sciences, Irvington, New York.
45. The DIFOTI UNIT was developed
as a diagnostic tool for early
detection of caries without the need
to use ionizing radiation.
46. The light from the DIFOTI probe is
positioned on the tooth to be assessed, then
the tooth is illuminated and the image on
the opposite non-illuminated surface is
captured by a digital electronic CCD
camera.
47. The data collected is then analysed by
computer software. The DIFOTI
appears to have the potential to detect
early carious lesions and assess their
progression.
48. MINI D CARIES
New caries detection portable device
Fiber optic principle
Requires no calibration .
It looks like a pen and diagnoses caries by
simply maintaining contact with the tooth
surface.
49. The presence of both occlusal and
interproximal caries is identified by 2
signals: audible and visual (green light
turns red ).
It is effective in a humid environment
and requires only a normal tooth
cleaning prior to use.
50. FLUOROSCENCE
The use of fluorescence for the detection
of caries dates back to 1929,when
Benedict observed the normal tooth
fluoresce under UV illumination and
suggested that this fluorescence might be
useful in the determination of dental
caries when monochromatic light is used
at 350, 410 and 530 nm on carious and
non carious teeth .
52. In the carious lesions, the emission
spectra shifts to more than 540nm or the
red range of electromagnetic spectrum.
54. Lussi et al (1998) in a study to develop a
new laser fluorescence system found that
the system might be a useful tool in the
detection of caries and they named this
system as diagnodent.
This system was patented by Kavo
(1999) and is based on the principle of
fluorescence.
55. Principle: It is a chair side, battery
powered quantitative- diode laser
fluorescence device.
The unit meets light at 655 nm
wavelength from a fiber optic bundle
directed onto the occlusal surface of a
tooth.
DIAGNOdent
pen 2190
56. A second fiber optic bundle receives the
reflected fluorescent light beam.
Changes caused by demineralization are
assigned a numeric value, which is
displayed on the monitor.
58. Operation: The instructions for the
DIAGNOdent system specify that the
occlusal area to be diagnosed be clean,
because plaque, tartar and discoloration
may give false values .
59. Criteria to assess caries progression
More recent cut-off limits recommended
for the DIAGNOdent device are:
0-13 : no caries
14-20: enamel caries and preventive
care advised
21-30: dentin caries and preventive or
operative care advised depending on the
caries risk assessment
>30 :operative care advised
60. The advantages of the fluorescence
method:
•Increased contrast between carious and
sound enamel makes earlier detection of
lesions possible.
•The depth of the lesion can be
estimated.
•Diagnosis of occlusal caries.
•No danger to patient or operator.
61. The disadvantages of the methods :
•Does not differentiate between active and
arrested caries.
•Does not differentiate between caries and
developmental defects with lower mineral
content.
•Secondary caries lesions associated with
metal fillings cannot be detected.
•The equipment is expensive.
64. ELECTRONIC RESISTANCE
METHOD:
The low conductance of the tooth is
primarily caused by the enamel. At
locations where the pore volume of the
enamel is larger, the electrical conductance
increases considerably.
65. Increased conductance or decreased
resistance are indicative of the presence of
hypo or demineralization.
The increased pore volume is due to
formation of microscopic cavities, which
are filled with saliva to form conductive
pathways for electrical transmission.
67. ULTRASONOGRAPHY:
It is the use of sound waves for the
detection and this offers continuous
potential as a diagnostic instrument.
68. Sonic velocity and specific acoustic
impedance can be determined for the
dentin and enamel as well as for the soft
tissue and bone.
The sites with visible cavitations and
dentinal radiolucencies produce echos
with a substantially higher amplitude .
69. DYES:
Dyes have a wide spread use in medicine,
biology and dentistry .
Uses:
•Identification of objects
•Indication of affected dental tissues
•Improvement of diagnostic methods&
•Enhancement of patient awareness.
71. Various dyes have been used in detection
of enamel caries (Calcian Zyglo ZL-22),
and dentin caries (Fuschin, Acid red
system and 9 –Aminoacridine).
72. Several dyes have been tested on
extracted teeth to differentiate the
layers and it was found by Fusayama
et al (1972) that -0.5% basic Fuschin in
propylene glycol is a successful dye for
differentiating infected dentin .
ROWLAND(1985) indicated acid red
instead of Fuschin because of its
cariogenic potential.
73. INFRARED CAMERA:
MATSUYAMA et al (1998) have used
an infrared camera to detect subsurface
lesions.
The infrared camera can be used to
measure the temperature drop on the
lesion surfaces caused by evaporation of
water in the body of lesion.
74. VIDEOSCOPE / ENDOSCOPE:
Endoscopic technique is based on
observing the fluorescence that occurs
when tooth is illuminated with blue light
in the wave length range of 400-500 nm.
White spot lesions appear darker than
enamel.
75. Allows visualization of small carious
lesions in the enamel.
Additionally, a camera can be used to
store the image . The integration of the
camera with the endoscope is called a
Videoscope.
77. OPTICAL COHERENCE
TOMOGRAPHY:
This technique utilizes broad bandwidth
light sources and advanced fiber optics to
achieve images.
It determines not only the presence of
decay but also the depth of caries
progression.
78. Traditionally, the performance of a
diagnostic test is evaluated in terms of its
validity (the degree to which a
measurement measures what it purports
to measure with reference to an
independent ‘gold standard’) and
reliability (the degree to which the results
obtained by a measurement procedure
can be replicated) [Last, 1995].
79. However, it is also important to assess the
consequences for the patient in response to
the diagnosis and/or treatment provided.
The evaluation should include
considerations about the potential
negative aspects for the patient as well as
considerations about the cost-effectiveness
of using the test.
80. Only when all the above issues have been
adequately addressed, should a new
diagnostic test or tool be implemented for
routine use in clinical practice
[Abramson, 1990].
81. REFERENCES
DIAGNOSIS AND RISK PREDICTION
OF DENTAL CARIES- VOL2; PER
AXELSSON
TEXTBOOK OF PEDODONTICS- THIRD
EDITION; SHOBHA TANDON
DENTISTRY FOR THE CHILD AND
ADOLESCENT- EIGTH EDITION
Mc DONALD, AVERY,
82. STURDEVANT’S ART AND SCIENCE OF
OPERATIVE DENTISTRY-FIFTH
EDITION
THEODORE M.
ROBERSON
HARALD O.HEYMANN
EDWARD J.SWIFT
DIAGNOSTIC TOOLS FOR EARLY
CARIES DETECTION, JADA
86. Nutritional analysis:
Frequent exposure to sucrose increases the
likelihood of plaque development by the
more cariogenic mutans streptococci
organisms.
The decrease in pH associated with
significant acidity may be due to either
sucrose or other acidic foodstuffs, both of
which may result in caries.
87. Salivary analysis:
Analyzing saliva provide important
information about appropriateness of
secretion rates and buffering capacity
and numbers of mutans streptococci and
lactobacilli.
High values of the number of colony
forming units may be helpful in
identifying high-risk patients.