by anjany chowdary MDS 1st year email: anjanychowdary@gmail.com

2. CARIES DIAGNOSIS
Guided By :
Dr Pallavi gopeshetti
Presented By:
Anjany chowdary

3. CONTENTS
• Introduction
• Definition and objective of caries diagnosis
• Caries risk assessment
Caries risk assessment tools
Caries activity tests
Cariogram
• Different methods for caries detection
Visual tactile methods
Radiography
Coventional radiographs
Xeroradiography
Digital enhancement
Digital subtraction radiography

4. Cont’d…..
Electronic Conductance and Impedance Measurement
Optical detection
FOTI
DIFOTI
transillumination with near infrared light
Laser induced florescence
Quantitative fluorescence
Infra red florescence
DIAGNOdent

5. Cont’d
Dyes
Endoscopy/videoscopy
Recent advances
Multi-photon imaging
Infrared fluorescence
Optical coherence tomography
Ultrasound
Tetrahertz imaging
Midwest caries I.D
Spectra caries detecting aid
Sporolife
Canary system
Cariesscan pro
Conclusion
References

6. INTRODUCTION
• The word diagnosis (plural, diagnoses) -Greek ‘‘dia’’
meaning ‘‘thorough’’ and ‘‘gnosis’’ meaning
‘‘knowledge’’.
• Thus, ‘‘to diagnose’’ implies that it is only through
knowledge about the disease that a diagnosis can be
established.

7. Diagnosis is an art and science that results from the synthesis
of scientific knowledge, clinical experience, intuition &
common sense
O
B
J
E
C
T
I
V
E
S
Lesions requiring surgical treatment
Lesions requiring non-surgical treatment
Persons at high risk for
developing caries

8. Ideal caries diagnostic test
Accurate
Sensitive
Specific
Reproducible
Reliable
Should not transfer S.mutans
Cost effective

9. RISK ASSESMENT TOOLS
Patient History
Clinical Examination
Nutritional analysis
Salivary analysis

10. PATIENT HISTORY

11. General
health
Mental/ph
-ysical
disability
Mucous
membra-
nes
Plaque
and
gingivaActive
carious
lesions
Clinical examination

12. NUTRITIONAL ANALYSIS
SAILAVARY ANALYSIS
Sucrose Plaque
Cariogenic
streptococcus
organisms
Secretion rate Buffering capacity
Number of both
Streptococcus
mutans &
lactobacilli

13. CARIES ACTIVITY TESTS

14. CARIES ACTIVITY TESTS
Identify high-risk groups
Motivate , monitor the effectiveness of
education
Serve as an index of the success of
therapeutic measures
Determine the need -preventive measures
Management- restorative procedures

15.  Lactobacillus colony count test
Introduced by HADLEY in 1933

16. paraffin stimulated Saliva is collected
1:10 ratio dilution made
.4 ml of dilution is spread on agar plate
Plates are incubated for 3-4 days at 37C
Lactobacillus
colonies on
agar

17. DENTOCULT LB
• In this test,Undiluted paraffin stimulated saliva is poured onto a plastic
slide coated with LBS agar.
• Excess saliva is allowed to drain off and slide is placed on a sterile tube
and incubated for 4 days at 37 degrees.

18. • Lactobacilli appear as small
whitish dots & no. on agar surface
is estimated by comparison with
chart
ADVANTAGE
A highly practical and greatly simplified method of estimating
lactobacilli is now available as DENTOCULT by Orion Diagnostica
More than 10⁵ High risk
Less than 10⁴ Low risk

19. Snyder Test
• Test devised in 1951
• Ability of micro organisms to form organic acids from carbohydrate
bactopeptone
dextrose
Nacl
Bromocresol green
agar
Saliva specimen secured
One tube of medium – heated to 100°C to
liquify the agar , and then cooled to 45°C
Saliva sample shaken for 3 minutes and 0.2
ml pippetted
Tube placed in incubator for 72 hrs at 37 C
medium

20. Colour observations
•Simple to carry out
•Requires one tube of medium and no
serial dilutions required
•Time consuming
•Sometimes colour changes are not so
clear

21. SWAB TEST
• Grainger et al – 1965
• Advantage – no collection of saliva is necessary
• Young children
• Principle – Snyder’s test – acidogenic & aciduric organisms

22. Oral flora – sampled by swabbing the buccal surfaces of teeth
with cotton applicator
Incubated in medium – 48 hrs
Change in pH – read on pH meter
pH CARIES ACTIVITY
5.0-4.6 INACTIVE
4.6-4.5 MILDLY ACTIVE
4.4-4.2 ACTIVE
4.1-4 VERY ACTIVE

23. ALBANS TEST
• Same formula as Snyder media
• Medium requires less agar
• Easier diffusion of saliva and acids without the necessity of melting
the medium
• Simpler sampling procedure
ADVANTAGES
Simplicity
Low cost
Motivational value
Good for indicating caries
inactivity
DISADVANTAGES
More armamentaria required
Based on subjective evaluation of
colour change that is not often
clear

24. Procedure
Test tube incubated for 4
days & daily observations
made for colour change
Patient drools unstimulated
saliva directly into the tube
5 ml of semisolid agar
INFERENCE
• Color change is scored from 0 to 4
• Score is based upon the colour
changes occuring from the top to the
bottom of the tube .
Score 0 Very immune
Score 1 immune
Score 2 slight
Score 3 medium
Score 4 high
1
2
3
4

25. Mutans Group of Streptococci Screening
Tests
Plaque/toothpick method
Saliva/ tongue blade method
S. mutans adherence method
S. mutans dip-slide methods
S. mutans replicate technique

26. Plaque/ Toothpick Method
• Semi –quantitative evaluation of mutans in saliva & plaque
• Plaque samples are collected form the gingival thrds of buccal tooth
surfaces and placed in ringers solution.
• Samples are shaken until homogenized.
• Plaque suspensions streaked across a mitis salivarius agar plate.
• After aerobic incubation at 37 c for 72 hrs, the cultures are examined
under microscope and total colonies in 10 fields are recorded.

27. SALIVA /TONGUE BLADE METHOD
•Sterile tongue blade – rotated in mouth ten times.
•Both sides of tongue blade are then pressed onto a MSB agar in
petridish
•Incubated at 48 hrs at 37°C

28. •Counts more than 100 CFU are proportional to greater than
106 CFU of mutans per ml of saliva by conventional methods
Advantage
It is a practical method for field studies as
it requires no transport media or dilution.

29. Strip Mutans Test
• Simple chairside technique – developed by Jensen& Bratthall
• Utilizes ability of S.mutans to grow on a hard surface – MSA broth
• Rounded plastic strip – sampling
• 15 min prior to sampling – 5 mg bacitracin – added to broth
• Plastic strip rotated in mouth withdrawn
• Strip – incubated in vial – 37°C – 48 hrs

30. colonies grade
negligible 0
Less than 105 1
from 105 to 106 2
More than 106 3
• S.mutans colonies appear as small blue dots –
density compared with standard chart.

31. S. Mutans ADHERENCE METHOD
This test categorizes salivary samples based on the ability of Streptococcus
mutans to adhere to glass surfaces when grown in sucrose containing broth
0.1 ml
saliva is
collected
Inoculated in
msb agar -60
Incubate
-d at 37
degrees-
24 hrs
Cells
adhering
macrosc-
opically are
observed

32. Streptococcus Mutans Replicate Technique
This technique localize Streptococcus mutans colonies on tooth surface
using a solid impression matrix composed primarily of sucrose and
commercial gum base.
Imprint of tooth
surface to be sampled
is obtained by pressing
the matrix against it.
Matrix is washed for
several seconds in
water to remove non
adherent cells and
saliva.
Matrices are placed in
liquid broth and
incubated at 37°C
overnight and examined
directly for overgrowth
of S. mutans colonies at
specific sites.

33. REDUCTASE TEST
• It measures the activity of the enzyme reductase in salivary
bacteria.
• The saliva is collected and mixed with a dye -
Diazoresorcinol. The change of color is noted in 15 minutes
Advantages
• No incubation required
• Time saving (quick
results)
Disadvantage
Results vary with time
after food intake and after
brushing

34. Salivary Buffer Capacity Test
• Salivary buffer capacity test can be quantitated using
either pH meter or color indicator.
• The test measures the quantity of acid in milliliters
required to lower the pH of saliva through an arbitrary
pH interval

35. Ten milliliter of
stimulated saliva
is collected at
least one hour
after eating.
5.0 ml of this
is taken in a
beaker.
The pH of saliva
is adjusted at 7.0
by addition of
lactic acid or
base.
Lactic acid is
further added
until pH 6 is
reached.
The amount of
lactic acid needed
to reduce the pH
from 7.0 to 6.0 is a
measure of buffer
capacity
PROCEDURE

36. ORA TEST
 The Ora test evaluates the oral microbial level.
It is based on the role of oxygen depletion by micro organisms in
expectorated milk samples
Does not
identify
any
specific
group of
organisms

37. • In this test 10 ml of sterile milk is rinsed in the oral
cavity for 30 seconds and the expectorate is collected
• 3.0 ml of this milk is transferred to a tube and 0.12 ml
of 0.1% methylene blue is added
• Milk attains blue colour
• Once oxygen gets utilized by aerobic organisms –
anaerobic environment is created
• Methylene blue – reduced to leucomethylene blue
• Colour of milk – changes from blue to white

38. THE CARISCREEN CARIES SUSCEPTABILITY TEST
• The CariScreen Caries Susceptibility Test by Oral BioTech is a simple
1-minute chairside bacterial test for assessing patients at risk for
caries
• Quick and painless

39. • CariScreen uses ATP bioluminescence to identify oral bacterial load
and has been proven to correlate with patients’ risk for decay.
• A swab sample of the plaque from patients teeth is taken it is
combined with special bioluminescence reagents within the swab, will
create a reaction that is then measured with the meter.
• The CariScreen will give a score between 0 and 9,999. A score under
1,500 is considered relatively healthy, while above that shows
considerable risk for decay.
• This technology not only allows you to measure patients’ risk for
decay today, but also helps measure their progress as they follow the
recommended protocols for reducing risk.

40. CARIOGRAM
Model for understanding interaction of various factors responsible
for caries.
Computer version presents  graphical picture  illustrates overall
caries risk scenario
Expresses extent to which different etiological factors affect caries risk

41. Combination of caries
experience and related
diseases.
Estimation
of the
'chance of
avoiding
caries‘
Combination of diet
contents and diet
frequency.
Combination of
amount of
plaque and
mutans
streptococci.
Combination of
fluoride
programme, saliva
secretion and
saliva buffer
capacity.

42. Patient
examined
Data 
collected
scored
Entered
computer
Pie
diagram

43. It is a prediction/risk assessment model  used in the daily routine
of the clinic
Illustrates caries-related factors and suggests actions to take
Affordable, user-friendly, and easy to understand
Tool for motivating the patient
Serve as a support for clinical decision making when selecting
preventive strategies for the patient
Tests easily be performed by the dental personnel and evaluated

44. THE ICEBERG CONCEPT
• Pitts- (1997)
• WHO -the shape & depth of carious lesion can
be scored as D1, D2, D3 and D4.
• Precision of caries diagnosis is illustrated as an
iceberg.

46. DIAGNOSTIC TOOLS

47. Chalky white lesions:“Hidden carious lesions”

48. When examining the patient for demineralized areas or early
cavitated lesions (also called “small carious lesions”) that have
the potential for remineralization we should look for:
Change in
color and
translucency
in enamel
Breaks in
enamel
surface
Grayish
white
discoloration
Shadowing
on proximal
surfaces
Black
discoloration
(arrested
caries)

49. Visual and tactile examination involves cleaning and
drying of the tooth and Use of explorers and probes.
The method of visual and tactile examination has
evolved since the time of Black

50. VISUAL METHOD
•ICDAS – 2 digit system (X-Y)
•X- status of the surfaces – unrestored, sealed, restored, crowned
•Y- measurement of visual changes
0- no or slight change in enamel translucency after
prolonged drying
1-first visual change in enamel- after prolonged drying- pits
or fissures
2- distinct visual change in enamel
3- Localised enamel breakdown in opaque or discoloured
enamel
4- underlying dark shadow from dentine
5- Distinct cavity with visible dentine
6- Extensive distinct cavity with visible dentin

51. Recording of cavitated and non-cavitated lesions (Pitts and
Fyffe, 1988)
Mouth mirror
Sickle probe
Classification
1. D1- enamel lesions, no cavity
2. D2- enamel lesions, cavity
3. D3- dentin lesions, cavity
4. D4- dentin lesions, cavity to the pulp
More realistic picture of total caries experience
Does not inform caries activity of lesion

52. LESION ACTIVITY ASSESSMENT
• Two surface features  activity (surface texture)
 integrity (presence/absence of cavity)
Active non-cavitated
Whitish/yellowish opaque surface
Loss of luster
Chalky or neon white
Rough surface when tip of sharp
probe moved across gently

53. • Active cavitated
Soft or leathery
Inactive non-cavitated
Shiny
Smooth on probing
Whitish to brownish
or black

54. Inactive cavitated
Shiny and
hard
Filling
Filling with active caries
Filling with inactive caries

55. The Visual-Tactile method (American
method):
Combination of light,
mirror and gentle
probing.
ADA criteria-
softened enamel
catches explorer and
resists its removal.
Allows the explorer
to penetrate
proximal surfaces
under moderateto
firm pressure.
Tooth is not dried or
cleaned.
Requires 3 min per
patient.

56. The Conventional Visual method- European
studies:
Detailed Visual examination is done.
Tooth is dried and examination takes about 10 min.
Criticizes the use of probes-
As probes may cause transmission of cariogenic bacteria
from infected sites, may trauamatize potentially
remineralization areas

57. “To probe or not to probe???”
Today's probing is limited to the removal of plaque
from the surface of an incipient lesion, thus enhancing
visibility.
In addition, it is used to assess the surface texture of a
lesion, an attribute that implies the activity of the
lesion.
 Blunt probe, manipulated at a 20–40° angle to the
surface, is being recommended against a sharp probe
acting perpendicular to the tooth surface.

58. 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.
Gap of 0.5-1mm can be gained within 48 hrs.
Non destructive, reversible and in expensive.

60. •Differentition
between cavitated
and non cavitated
lesions
Buccolingual
extension of the lesion
Non invasive and no
radiation
•Additional visits
•Occasional
discomforts
•Danger of accidental
inhalation
•Exacerbation of
gingival inflammation
ADVANTAGES
DISADVANTAGES

62. RADIOGRAPHIC METHODS

63. Characteristics of proper radiograph:
Image-all parts seen, no overlap, natural size
Area covered-sufficient surrounding area
Density
Contrast
Definition and sharpness all should be adequate

64. Common Mistakes:
cone cuts, overlapping, failure to include required areas
Advantages of radiographs:
•Disclose sites inaccessible to other methods
•Depth – evaluated and scored
•Permanent record- progression or regression
•Non-invasive

65. RADIOGRAPHY: LIMITATIONS
Two dimensional
Standardization
Earliest stage not disclosed
Subjective
Non cavitated lesions on root , detecting
buccal/lingual caries are difficult to diagnose

66. CONVENTIONAL RADIOGRAPHS
• Intraoral periapical radiographs
• Occlusal radiographs
• Bitewing radiographs
• OPG

67. • Type of x-ray in which a picture of the body is recorded on plate rather
than on film.
• Technique in which image is recorded on alluminium plate coated with
a layer of selenium particles.
XERORADIOGRAPHY
selenium
particles

uniform
electric
charge
Stored in
a unit
“condition
er”
Selective
dischrge
of
particles
Latent
image 
positive
image

68. •Edge exposure so small structures and
areas of subtle density differences are
visible
•Offers convenience
•Reduction in radiation dose
•Economical
•Electric charge over the film discomfort
to the aptient
• Positioning difficulties
• Image artefacts (discharge effects) are
more

69. Xero-radiography is twice as sensitive as conventional D-
speed films. The phenomenon of ‘Edge enhancement’ is
possible with this technique. Edge enhancement means
differentiating areas of different densities especially at the
margins or edges.

70. Digital radiography
DIGITAL IMAGE: Set of discrete sensors and pixels

71. •In digital radiography, instead of the silver halide grain the
image is constructed using pixels or small light sensitive
elements.
•The pixels can be a range of shades of grey depending on the
exposure, and are arranged in grids and rows on the sensor,
unlike the random distribution of the crystals in standard film.

72. RVG system (Radio Visio Graphy)
Four main components
• An X-ray set with special timer
• An intra oral sensor
• A display processing unit
• A printer
Special electronic timer to
give the accurately
controlled, short exposure
times required.
An intensifying screen
25mm×16mm housed in
a rigid plastic casing
40.6mm long × 22.8mm
wide×14mm thick.
Behind the screen is an
array of optical fibers.
Number of controls
Allows manipulation of the
image

73. • There are two systems available, one produces the
image immediately on the monitor post-exposure and
is therefore called direct imaging.
• The second has an intermediate phase, whereby the
image is produced on the monitor following scanning
by a laser. This is known as semi-direct imaging.

74. Direct imaging
Sensor Computer
signal is sampled at regular
intervals.
Output of each pixel
quantified - converted to
numbers by a frame
grabber within the
computer

75. Semi-direct
imaging
Sensor Scanner Computer
•Scanner stimulates the phosphor plate and
stores a record of the number of light
photons detected.
•Lasers  centered around the 600nm band

76. CHARGED COUPLED DEVICE
Semiconductor made up of metal oxide such as
silicon that is coated with xray senitive receptors
Silicon chip- light sensitive pixels – electron –
bonded by covalent bond.
Light photons strike- electron is displaced-
electric charge- analog signal- image
Transfer of electron in sequential manner- bucket
brigade.

77. ADVANTAGES
Dose reduction- up to 90 percent compared to E-speed film
Image manipulation - greatest diagnostic value and suppressing the rest.
Contrast enhancement - compensate for over or under exposure
Measurements - Digital calipers, rulers and protractors
3-D reconstruction - to visualizing facial fractures in all three dimensions.
Time - displayed at the chair side
Storage - hold over 30,000 images
Teleradiology - compression techniques and sent via e-mail
Environment friendly -capable of being reused for many times

78. DISADVANTAGES
•Cost
•Sensor dimensions - bulky for the CCD system and
awkward
•Medico-legal - ability to manipulate the images for
fraudulent purposes.
•Cross-infection control – many times usage

79. Subtraction Radiography
When two radiographs are recorded with at least partly controlled
projection angles, the information from the most recent one may be
digitally subtracted from that of the former.
Optimally, all unchanged anatomical background structures will
cancel and unchanged areas will be displayed in a neutral grey
shade in the subtraction image.
Areas with mineral loss are conventionally displayed in darker
shades of gray, while areas of gain appear lighter than the
background.

81. Electronic Conductance and Impedance
Measurement
• Magitot in 1878 :
• BASIS:
Intact enamel has very high resistance and limited or no
conductivity.
Carious or demineralized enamel -measurable
conductivity that will increase with increasing
demineralization
Current is applied with one electrode on the tooth and
conductance is obtained with contra electrode.

82. • CIRCUIT:
Device has a –cord which is attached to a –probe that is placed on
the –tooth.
The patient holds a hand held earth-unit –which is connected to a
cord that – leads back to the device.

83. Moisten the teeth
Hold the reference
electrode-
Probe tip -on the site
Stable reading -audible
sign -
Mean of the two
readings
PROCEDURE

84. Devices using electrical conductance property
• AC ohmmeter
• Caries meter- L
• Vanguard electronic caries detector
• Electronic caries monitor
• Electrical impedance tomography
• Electrochemical impedance spectroscopy

85. The Vanguard Electronic Caries Detector
•Electrical conductivity is expressed numerically on a
scale form 0 to 9 (sound tooth to demineralised enamel)
Indicators for Caries L meter are 4 coloured lights
Green- No caries
Yellow- Enamel
Orange- Dentin caries
Red - Pulpal involvement

86. ADVANTAGES:
Very effective in
detecting early pit and
fissure caries
Can monitor the
progress of caries
during caries control
programmes.

87. LIMITATIONS
Can only recognise demineralisation and caries specifically
Hypomineralisation areas of developmental origin or caries
will give similar results.
Enamel cracks leads to false posititves
Sharp metal explorer can cause traumatic defects
Time consuming procedure.

88. OPTICAL METHODS

89. FIBRE OPTIC TRANSILLUMINATION
Evolved due to the growing concerns
about ionizing radiations.
Basis:-Decayed matter scatters light
more strongly and has lower index of
light transmission.
Cleaning
• Compressed
air
Flashlight
• Tip 0.5 mm
• 150 W
halogen
lamp

90. •For anteriors
• The probe should be brought from the labio-cervical aspect
at an angle of 45 degree to the approximal surfaces pointing
apically while looking for dark shadows in the enamel or
dentine that is observed through the lingual mirror.
•Anterior caries appear as well defined dark shadow in the
class III region of the tooth

91. Posterior teeth
•The probe should be brought from the buccal and
lingual aspect at an angle of 45 degree to the
approximal surfaces pointing apically.
•when a Triangular shaped shadow is seen it
indicates the presence of proximal decay.
Can detect Enamel– crazing,
cracks in tooth

92. Advantages:-
• No radiation hazards
• Simple and comfortable
• Not time consuming
• Lesions not diagnosed by radiographs, can be diagnosed
by this
Disadvantages:-
• Permanent records difficult to maintain
• Subjected to intra and inter observer variations
• Difficult to locate probe in certain areas.

93. DIFOTI

94. • DIFOTI was developed to reduce the shortcomings of
FOTI
• Combining FOTI + a digital CCD camera.
Light propagates from an optical fibre
through the tooth to an unilluminated
surface.
The image is acquired by a digital
electronic CCD camera
Image is then analyzed by the computer.

95. Image relay mirror which sends
transmitted light to the ccd imaging
camera in the hand peice

96. Early tooth decay Fractures
Excavation
Leakage and fracture around old
amalgam restorations

97. ADVANTAGES
• Doesn’t need film, ionizing radiations
• Non invasive
• Detects early caries
• Quality of the image can be controlled
• More sensitive
DISADVANTAGES
• Cant determine the depth of lesion
• Overdiagnosis can occur due to low specificity
• White spots can be mistaken for cavitations as they
appear dark

98. QUANTITATIVE LASER FLUORESCENCE
• Quantitative laser or light induced flourescence.
• Bejelkhagen & sundstrom (1981).

99. ADVANTAGES:
• Incipient lesions can be
detected.
LIMITATIONS:
• Enamel lesions and those extending to
dentin.
• Decay, hypoplasia and unusual
anatomical features.
• Wet/dry state of the tooth &
presence of plaque, calculus and/or
staining on the tooth surface.

100. DIAGNODENT
• KaVo DIAGNOdent (KaVo, Biberach, Germany), introduced
laser-based instrument, developed for detection and
quantification of dental caries on smooth and occlusal
surfaces.
• Red light- 655 wavelength
• Intensity of fluorescence – 0-99

101. •For the use of diagnodent on the occlusal surfaces, the instrument
has to be tilted around the measuring site.
•This ensures that the tip picks up fluorescence from the slopes of
the fissure walls where the carious process is believed to originate.
• The limitation with this device is that Very initial lesion cant be
detected as no fluorophores due to absence of bacteria- so no
result
• Also Moisture conditions affect results.

102. • It is a pen like device with detachable tips of different
diameters- occlusal and proximal.
• The light is transmitted through a descendent optic fiber to
a hand-held probe with a bevelled tip .

103. • The emitted fluorescence, as well as back-scattered ambient
light, is collected through the tip through a second fibre optic
bundle (that surround the 1st bundle which emits the red
light), and passed to a photo-diode detector.

104. Each patient
must be
individually
calibrated by
setting a base
level on a
healthy tooth.
The signal is
finally processed
and presented on
the display as an
integer between
0 and 99 and
also
accoustically.
5-25: INITIAL
LESIONS
25-35:EARLY
DENTINAL
CARIES
35: ADVANCED
DENTINAL
CARIES

105. FALSE POSITIVES
• Organic plug
• Composite restorations
• Calculus
• Impacted food in the fissures
• Stained enamel
• Remineralized enamel

106. Detects
Recurrent
Caries
Residual
Caries
Caries
Under
Sealants
Root
Caries
Subgingiv-
al Calcus

107. DYES ENHACED LASER FLUORESCENCE
• Dyes can facilitate caries detection and
visualization.
• An absorbing dye can be introduced, enhancing
the colour contrast between the lesion and the
surrounding tooth structures.

108.  Dyes should fulfil the following criteria before being
recommended for clinical use.
 Should be absolutely safe for intra oral use.
 Should be specific and stain only the tissues it is
intended to stain.
 Should be easily removed and not lead to
permanent staining.

109. Various dyes have been tried to detect carious enamel,
each having some advantages and disadvantages
• Procion dyes
To stain enamel lesions
Staining – irreversible
• Calcein
To measure the infiltration into carious enamel
Complexes with calcium and remains bound in the lesion.

110. • 0.5% Basic fuchsin in propylene glycol
Dyes have been tried to differentiate between these two zones of
dentin caries.
It has proved to be successful for the purpose.
Basic fuchsin dye was considered to be carcinogenic; therefore it has
been replaced by acid red and methylene blue.
• Acid red is specific and more reliable -complete removal
of bacterially infected and soft carious dentine.
• Methylene blue is used but it is slightly toxic

111. • 10% Brilliant blue.
• Used to enhance the diagnostic quality of fiber optic
transillumination. Small incipient lesions were more
detectable
• Other fluorescent dyes:
• Fluorol 7GA
• Pyrromethane556-can detect only 2 hr of demineralization
• Sodium Fluorescein

112. ENDOSCOPE
• Endoscopic technique is based on observing the
fluorescence that occurs when tooth is illuminated with
blue light in the wavelength range of 400-500 nm.
• Difference is seen in the fluorescence of sound enamel
and carious enamel.
• White spot lesions appear darker than normal enamel

113. • Helps in detecting small carious lesions
• Video camera mounted on custom-made metal mirror
holder
• The integration of the camera with the endoscope is
called a videoscope.
• This is designed in such a way that the image of the
surface of enamel can be viewed directly over a screen

114. ADVANTAGES
• Provides a magnified
image
• Clinically feasible
• Early diagnosis of
caries
DISADVANTAGES
• Requires drying and
isolation of teeth
• Time consuming
• Expensive

115. Recent advances

116. MULTIPHOTON IMAGING
• Girkin et al
• Infrared light ( =850 nm) been used
• In the multi-photon technique, two infrared photons (with half
the energy of the blue photon) are absorbed simultaneously.
• Caries will appear as a dark form within a brightly fluorescing
tooth.
• Currently, the technique has been performed only on extracted
teeth,

117. • Images from the tooth :
• Form a three-dimensional image.
• Displayed in its negative form -caries appears bright within a
dark tooth
• Multi-photon imaging is able to collect information from
caries lesions up to 500 microns in depth.

118. INFRARED THERMOGRAPHY
Measure changes in thermal energy when fluid is lost from a lesion by
evaporation.
Indium/antimony thermal sensors- detect temperature changes in the
order of 0.025°C.
With a constant flow of air over the surface of the tooth, the change in
temperature of the lesion is compared with that of the surrounding
sound tooth structure
Source-to-sensor distance is 20 cm, and the time taken -2 min.
The technique has not been used intra-orally.
Problems will exist in relation to variations in the temperature of the
mouth with respiration or fluid evaporation from other oral surfaces.
The source-to-specimen distance - unsuitable for posterior teeth.

119. OPTICAL COHERENCE TOMOGRAPHY
• It is a method for imaging transparent and
semitransparent structures
• Uses (Super Luminescent Diodes) as the light
source
• Wavelength of light is in the range of 840 to
1310nm

120. • SLD(Super Luminescent Diodes) passes through a beam splitter to
divide it into two coherent beams of light .
• One beam is called the sample beam and the other, the reference
beam.
• The sample beam goes into the tooth and will be scattered according to
the nature of the tissue
• Carious tissue scatters light to a greater extent than does sound tooth
structure.
• Variation in scattering measured in relation to depth from a single point
on the tooth surface is called an "A-scan".
• Several A-scans along a line produces information from a 'slice' of tooth
tissue, which is the tomogram
• The movement along the A scan  B- scan
• The reference beam is transferred to a movable mirror connected to a
photodetector

121. SLD
840 to 1310 nm
Reference
beam
Sample
beam
Beam splitter
Tooth and will
be scattered
according to the
nature of the
tissue
Carious tissue
scatters light to
a greater extent
than does
sound tooth
structure.
•Variation in
scattering "A-
scan".
Several A-
scans along a
line -B-scan".
Movable mirror
Photodetector

122. TERAHERTZ IMAGING
• This method of imaging uses waves with terahertz frequency
(=1012 Hz or a wavelength of approximately 30 μm).
• This wave-form is short enough to provide reasonable
resolution but long enough to prevent serious loss of signal due
to scattering
• For an image to be obtained by terahertz irradiation, the object
is placed in the path of the terahertz beam.
• The terahertz beam can be scanned over the surface of an
object.
• Terahertz images are recorded using a CCD detector and
displayeD on computer screen

123. • Dental applications for this technique have been
limited but promising.
• since terahertz waves are strongly absorbed by
water, a potential complication in the mouth
• Still a developing diagnostic aid

124. ULTRASOUND
Detects early carious
lesions on smooth
surface
Demineralisation of
natural enamel
ultrasound pulse
echo technique.
Definite corelation
between mineral
content of a body
and the echo it
produces.
Specific acoustic
impedance
Ultrasonic probe
longitudanal waves to
surface of the tooth and
also serves the function of
receiving the waves.

125. • Normal enamel- no echo
• White spot lesion- weak surface echo
• Areas with cavitation- echoes of higher amplitude
• More sensitive than visual-tactile method but not
quantitative

126. MAGNETIC RESONANCE
MRI + MRMI Enhanced resolution.
Technique uses a moderate magnetic field
In the laboratory capable of producing highly accurate 3-d
reconstructions of teeth and carious lesions as confirmed by
histological investigations.
Not available for clinical application

127. SPECTRA CARIES DETECTION AID
•Spectra uses fluorescence to detect caries in fissures and
smooth surfaces that may go unnoticed in X-ray images
•Carious regions appear red, while healthy enamel appears
green
•After capturing the image within existing imaging software,
the extent of the decay will be interpolated and indicated in
two ways:
1. The color will be either blue, red, orange or yellow
2. A numerical indicator between 0 and 5 will be shown

128. ADVANTAGES
Impressive, information-rich images enhance case acceptance
Spectra can detect decay hidden between the margins of existing
composite and amalgam restorations
The Doppler radar-like images are easily understood and allow you
to clearly show your patients how early intervention helps them
Spectra guides us through the caries removal process from pre-to
post-procedure, ensuring that all carious dentin has been removed

129. MIDWEST CARIES I.D(Dentsply)
Portable,
handheld device
Combination of
LED and fiber
optic technologies
Both occlusal
(90%)&
interproximal
caries(82%)
An audible tone,
and a visual signal
.
Clean tooth
surface, free of
plaque and
calculus.
Full mouth scan in
under 2 minutes.
Unit lifespan of
over 100 patients.
Autoclavable
outer housing

130. SPOROLIFE
• New imaging fluorescence device aiding in the diagnosis and
treatment of caries
• The auto fluorescence technology in SOPROLife allows us to
detect decay, even in its earliest stages, which can often be
missed by the eyes or by x-rays.
• The light penetrates the enamel outer layer and shows the
healthy dentin in a green color and the decayed dentin in red.
• SOPROLife is free from ultraviolet or ionizing rays.

131. THE CANARY SYSTEM
• The Canary System is a device for the early detection and
monitoring of tooth decay.
• It can detect decay on smooth enamel surfaces, root surfaces,
biting surfaces, between teeth and around existing amalgam
or composite fillings.
• It is a pain-free, safe and non-invasive early detection system
built on years of thorough research.

132. How does The Canary System work
• Uses a low-power, pulsating laser light to scan
• Laser light is converted into luminescence and there is
a release of heat.
• Simultaneous measurement of the reflected heat and
light provides information on the presence and extent
of tooth decay

133. THE CarieScan PRO
• Designed and manufactured in the UK, The CarieScan PRO quickly
and easily identifies both decay and healthy tooth structure.
• The PRO boasts a combined accuracy rate of 94.8%, and takes less
than a second per tooth to provide a reading.
• Easy for both patient and clinician to understand
• the device provides a numerical reading for each site analysed,
supplemented by a colour and high, medium or low reading.
• Multiple readings can be taken per tooth for incredible accuracy

134. • Key Features:
Uses electrical impendence to provide incredibly accurate and
reliable results that is 94.8% Combined Accuracy, and fewer than
7% false positives
Reduces the need for potentially harmful x-rays, which saves
time and cost to patient
Repeatable data aids ongoing monitoring,
No need for calibration, readings can be taken consecutively at
speed
Easy to use, handheld device for fantastic usability

135. CONCLUSION
With the changing nature of the disease process ,use of
current traditional methods of detecting dental caries
becoming more and more difficult.
Although currently there is no single diagnostic method on
the horizon that can reliably detect pre-cavitated carious
lesions on all tooth surfaces.
With continued research, the novel new methods will
provide the high degree of sensitivity and specificity
needed to detect early dental caries.

136. REFERENCES
 Art and Science of Operative dentistry. Sturdevant 5th edition.
 Operative Dentistry: modern theory and practice M. A Marzouk
 Hidden and incipient carious lesions: DCNA 2005.
 Cariology: Newburn
 Diagnosis of Caries: Axelsson
 Dental Caries And its management(2nd edition): Fejerskov and
Edwina Kidd
 Dental Caries Diagnosis: DCNA 1999
 Detection activity Assessment and diagnosis of dental caries:
DCNA 2010