CARIES DIAGNOSIS ALONG WITH NEW TRENDS

1. CARIES DIAGNOSIS
Dr POOJA JAYAN
1st Year PG
DEPARTMENT OF CONSERVATIVE DENTISTRY AND ENDODONTICS
ST GREGORIOS DENTAL COLLEGE

2. CONTENTS
Introduction
Definitions
Diagnosis for caries
Caries activity tests
Conclusion

3. INTRODUCTION

4. “The eyes do not see what the mind doesn't know”
Diagnosis is to distinguish irregularities and other issues of concern based upon a patient’s examination and interview.
In Greek “dia” means thoroughly and “gignoska” means to know.
DIAGNOSIS

5. DIAGNOSIS OF CARIES

6. DIAGNOSIS OF DENTAL CARIES
Its the art or act of distinguishing one disease from another.
Modern management of caries: based on 3 major components
 Prevention
 Control
 Treatment
A diagnostic method should allow for detection of the disease in the earliest stages and for all pathological
changes attributed to the disease to be determined.

7. Objectives of diagnosis:
 Identifying lesions which do not require restorations
 Identifying lesions requiring restorations.
 Persons at high risk for developing caries
Sensitivity: Ability of test to diagnose disease correctly when disease is actually present
Specificity: Rule out disease correctly when it is truly absent
Thus diagnosis is done using:
 Clinical criteria
 Tools
 Newer refined diagnostic tools
DIAGNOSIS OF DENTAL CARIES

8. According to WHO the shape & depth of carious lesion can be scored
 D1 : enamel lesion, no cavity
 D2 : enamel lesion, cavity
 D3 : dentin lesion, cavity
 D4 : dentin lesion, cavity to pulp
THE ICEBERG CONCEPT
Pitts (1997) – precision of caries diagnosis is illustrated as an iceberg.

9. 1. X-rays
 IOPA/Bitewings
 Digital imaging
 Digital subtraction radiography
 Tuned aperture computed radiography
2. Visible light
 fiber optic trans-illumination
 Quantitative light-induced fluorescence
CLASSIFICATION - based on physical properties Mansson etal
3. Laser light-laser fluorescence measurement
(Diognodent)
4. Electric current –
Electric conductance measurement
Electric impedance measurement.
5. Ultrasound –ultrasound caries detector

10. Visual Examination: Mouth mirror, probe(explorer), good light.
Conventional method.
Every tooth is dried and examined
Tactile evidence
• Roughness or softness of the tooth with explorer.
• Penetration and resistance to removal with an explorer tip.
VISUAL AND TACTILE EXAMINATION

11. 0 - No caries or radiolucency after air drying.
1 - White/brown opacity hardly visible on wet surface/distinctly visible on dry surface
2 - Opacity visibly distinct with out air drying
3 - Localized enamel breakdown in opaque or discolored enamel or grayish
discoloration from dentin.
4 – Cavitation exposing the dentin
CLASSIFICTION BASED ON VISUAL EXAMINATION

12.  Limitations: cant detect non cavitated lesions in dentin on posterior proximal surfaces.
 American method: softened enamel catches the explorer tip and resists removal
 Allows the explorer to penetrate under mild pressure.
 No tooth drying
 European method: no probe is used
 Tooth is dried and visual examination done.
 Meticulous clinical visual method: cleaning, drying, and flossing-to disclose more lesions
COMMONLY USED VISUAL METHODS

13. The visual method with temporary Elective Tooth
Separation.
.
TOOTH SEPARATION & FLOSS

14. RADIOGRAPHY : gold standard
Techniques
Intra Oral
Parallel Bisecting Angle
Extra Oral

15. Radiographic Appearance Of The Caries:
• Initial enamel - small radiolucent notch.
• Advanced lesions – Diffuse triangle with base to surface of the tooth-in enamel.
Appears as triangle with base towards DEJ
Advantages :
Discloses sites inaccessible to other methods.
Detects at early , reversible stage and permanent record.
RADIOGRAPHY

16. RADIOGRAPHY
Depth of lesion can be evaluated and scored by index given by Grondahl et al (1977)
• 0 : no radiographic change in enamel
• 1 : radiographic change in enamel
• 2 : radiolucency extending to enamel
• 3 : radiolucency extending half way to dentin
• 4 : radiolucency close to pulp

17. • Used to detect proximal caries
• Important to detect incipient lesions at contact points.
• Detection of secondary caries below restorations
• Cervical margins of restoration
• Shows alveolar crest height and lamina dura
• Estimates size of pulp chambers.
BITEWING RADIOGRAPHY

18. Limitations:
• 2D image of a 3D object
• Standardization needed for accurate reproducibility
• Does not distinguish between sound, subsurface & cavitated lesions
• Non cavitated lesions on root difficult to diagnose
• demineralization of Occlusal caries not seen until it reaches DEJ
• Unavoidable hazard of ionizing radiation
RADIOGRAPHY

19. • Technique simulates that of photo-copying
• Xerographic films to record the images produced by X-rays
Image recorded on aluminum plate with a layer of selenium particles and is given a uniform
electrostatic charge
• X-rays-passes through film- causes the discharge of particles producing a latent image- converted
in a processing unit to positive image.
• Advantages
• Edge enhancement
• Less radiation
• Economical
XERO RADIOGRAPHY
• Disadvantages
• Electrical charge may cause discomfort to patients
• Exposure time varies with thickness of film
• Process of development cannot be delayed more
than 15min

20. • Principle: works on a CCD which is electronically connected to computer
• Image is formed and represented by a spatially distant set of discrete sensors and pixels
• CCD-4 major components
• X-ray image detection
• Digitalization
• Image processing
• Image display
• CCD-is a semi-conductor made of metal oxide silicon coated with x-ray sensitive photons
• Charge coupling is a process whereby the number of electrons deposited in each pixel are
transferred from one well to the next in a sequential manner to a read-out amplifier for
image display on the monitor.
DIGITAL IMAGING

21. Egs: Durr Vista Ray Trophy RVG
CHARGE-COUPLED DEVICE : CCD

22. • Advantages :
• No dark room processing
• Reduced radiation dose
• Image manipulation
• Ability to enlarge specific area
• Dis-advantages :
• Cost of the system
• Life expectancy is not fixed
DIGITAL IMAGING

23. • Principle: Optimally, all unchanged anatomical background structures will cancel, and
changed areas will be displayed in a neutral grey shade in the subtraction image.
• Loss of bone appear in darker shades of grey, and areas of gain appear lighter than the
background.
Advantages:
• Broader latitude of enhancement
• Reduced in radiation dosage
Dis-advantage:
• Inability to produce the same geometry
• Density and contrast are not proper
DIGITAL SUBTRACTION RADIOLOGY

24. • Principle: decayed matter scatter light more strongly and appear as darkened shadows
• Light is absorbed more and lower index of light transmission due to disruption of crystalline
structure of enamel and dentin
• Compressed air used- better visualization
FIBRE OPTIC TRANSILLUMINATION (FOTI)

25. • Used in the anterior and the premolar region
• Used to detect-enamel crazing - cracks in the tooth
• Advantages – no hazard of radiation, simple and comfortable for patients, not time
consuming
• Disadvantages – limited only for enamel caries detection, difficult to locate probe in certain
areas, permanent records difficult to maintain
FIBRE OPTIC TRANSILLUMINATION

26. Components:
• handpieces
• Disposable mouth piece
• Foot control for selecting the images
• Computer
DIFOTI: combines FOTI and digital camera

27. • Mechanism: light propagates from optical fiber to the tooth surface-the area of
demineralization scatter light and appear dark
• This image is acquired through CCD camera-and the lesion can be monitored
DIFOTI
Correct placement of proximal mouthpiece. Position the hand piece Image review

28. ADVANTAGES
• Doesn’t need ionizing radiation
• Instant images
• Non invasive
• Early caries ,hidden caries
• No film, film processing, mounting, and storage.
• more sensitive than conventional radiographs
DIFOTI

29. Limitations:
• Cant determine the depth of lesion
• Learning curve required
• White spots can be mistaken for cavitations
DIFOTI

30. The aim of the present study was to compare the diagnostic accuracy/efficacy of digital imaging fiber-optic
transillumination (DIFOTI) with film and digital radiography, in detection of approximal caries lesions. One
hundred and twelve approximal surfaces were scored for caries, using DIFOTI images film and digital
radiographs. All three sets of images were examined twice by 8 observers, with a minimal interval of one
week between examinations. Validation of histological sections served as a reference standard.
Reproducibility, based on intra- and interobserver agreement, was similar for all three methods. At
diagnostic threshold D1 (enamel and dentin caries), DIFOTI showed significantly higher sensitivity, but
differences in specificity between methods were nonsignificant. Diagnostic accuracy in the form of area
under the receiver operating characteristic curve (AUC) was significantly higher for DIFOTI. At diagnostic
threshold D3 (dentin caries), the differences in sensitivity and AUC among methods were nonsignificant,
but DIFOTI showed significantly lower specificity. Compared with the radiographs, DIFOTI showed closer
agreement, expressed as weighted kappa values, with the reference standard. The results show that under
in vitro conditions, the diagnostic accuracy of DIFOTI in detecting early approximal enamel lesions is greater
than that of film and digital radiography, while the potential for detecting lesions in dentin is similar for all
three methods.
Approximal Caries Detection by DIFOTI: In Vitro Comparison of Diagnostic
Accuracy/Efficacy with Film and Digital Radiography
A. ́ Astvaldsd ́ ottir, K. Ahlund, W. P. Holbrook, B. de Verdierand S. Tranæus
International Journal of Dentistry Volume 2012,

31. Consists of:
• Light source
• Measuring and reference points
• Detection part
Used for Quantification of caries lesions on smooth surfaces
Light though a fibre bundle - tip of hand piece – tooth – reflected light is collected
Scattering coefficient values are determined.
OPTICAL CARIES MONITOR

32. • Principle:
• sound enamel has high resistance to current flow
• carious enamel-porous filled with saliva has low resistance and high conductance
• Conductance increases as lesion progress
• Meters can be calibrated to depth and extent
ELECTRICAL CONDUCTANCE (FIXED FREQUENCY) METHOD

33. • Circuit –cord attached to a probe which is placed on the tooth-Patient holds it to
complete the circuit
• The electrical conductance between the fissure and area of high conductance are
converted to ordinal scale
• Examples
• Vangaurd Electronic Caries Detector
• Caries meter L
Indicators for Caries L meter are 4 colored lights
• Green- No caries
• Yellow- Enamel caries
• Orange- Dentinal caries
• Red - Pulpal involvement
ELECTRICAL CONDUCTANCE (FIXED FREQUENCY) METHOD

34. Indications:
• Pit and fissure caries
• Failure of fissure sealants
Drawbacks
• Results vary due to size of tip used
• Results depend on the type of current used
• Teeth should be dry
False positive results:
• Immature teeth
• Cracks in enamel
ELECTRICAL CONDUCTANCE (FIXED FREQUENCY) METHOD

35. • Hibst and Gall (1998) – red light (638-655nm) induced fluorescence could differentiate
between sound and carious tooth tissue.
DIAGNODENT DEVICE

36. • Light from Diode laser (wl=655nm). Light transmitted through descendant optic fiber to
hand-held probe – bevelled tip with fiber-optic eye.
• Organic, inorganic molecules absorb light – fluorescence occurs within infrared spectra.
• Signal processed and displayed as an integer between 0 and 99.
• To collect fluorescence from maximum extension of carious lesions on occlusal surfaces –
instrument to be tilted around measuring site – tip picks up fluorescence from slopes of
fissure walls.
• Lussi et al (2001) – good to excellent sensitivity, excellent reproducibility
DIAGNODENT DEVICE

37. Mechanism of DIAGNODENT DEVICE
Readings (Tam & McComb, J Can Dent Assoc, 2001):
• 5-25: initial lesions
• 25-35:early dentinal caries
• > 35: advanced dentinal caries

38. DIAGNODENT DEVICE

39. DIAGNODENT DEVICE - Advantages

40. DIAGNODENT DEVICE - Limitations
• Doesn’t differentiate between decay , hypoplasia, or unusual anatomical form.
• Cant differentiate between active and inactive lesions
• Sensitive to stains, deposits , calculus. Tooth should be clean and dry
• Accuracy affected by existing restoration or fissure sealants
Kavo prophyflex

41. QUANTITATIVE LASER/LIGHT FLUORESCENCE (QLF)
• Bejelkhagen & Sundstrom (1981)
• Mechanism : demineralization of dental hard tissues causes loss of its
autofluorescence. Fluorescence radiance of carious lesion lower than sound
enamel.
• Argon laser-488 nm
• Xenon arc lamp – 370 nm

42. QUANTITATIVE LASER/LIGHT FLUORESCENCE
Blue light is used to illuminate the tooth which causes the tooth to fluoresce in
yellow, green or red.
• Demineralized areas-dark
Intensity of red fluorescence is related to the activity of bacteria.
• Advantages:
• Incipient lesions – 25 μm
• De Josselin De Jong (1992)-determines amount of mineral loss
• Monitor changes in lesions

43. QLF
Limitations:
• On accessible smooth surfaces only
• Cant discriminate between enamel & dentin lesions
• Not suitable for dentin demineralization
• Cant differentiate between decay , hypoplasia
• presence of plaque, calculus

44. DYES USED FOR CARIES DIAGNOSIS
• Absorbing dye introduced-enhances the color contrast between diseased and
healthy tooth
• Dyes should be
• Safe for intra-oral use
• Stain the tissues that are diseased
• Should be easily removed
• Dyes used for enamel:
• Procoin
• Calcein-reacts with calcium and bounds to the lesion
• Brilliant blue-used with FOTI

45. DYES USED FOR CARIES DIAGNOSIS
• Carious dentin - 2 layers
• Outer layer soft and decalcified, cannot be re-mineralised
• Inner layer, hard ,can be re-mineralised
• Dyes used- 0.5% basic fuchsin in propylene glycol
• Outer layer-denatured collagen is stained
• Inner layer-not stained
• Replaced by
• Acid red
• Methylene blue

46. Influence of caries detection dye on bond strength of sound and carious
affected dentin: An in-vitro study
Udai Pratp Singh, AP Tikku, Anil Chandra, Kapil Loomba1, Lalit Chandra Boruah
ABSTRACT
Objectives: The objective of this study was to evaluate the influence of caries detection dye on the in-vitro tensile bond
strength of adhesive materials to sound and carious affected dentin.
Materials and Methods: Forty healthy and carious human molars were ground to expose superficial sound dentin and carious affected
dentin. Caries Detector dye was applied to sound and carious affected dentin and rinsed. Subsequently the dentin was etched with
37% phosphoric acid and rinsed leaving a moist dentin surface. The adhesive (Single bond) was applied in single layers and light cured.
A posterior composite (Filtek Z 250) were used to prepare the bond strength specimens with a 3 mm in diameter bonding area. Control
and experimental groups were made with and without application of dye respectively. Each group includes both sound and carious
affected dentin. After 24 hour immersion in distilled water, tensile bond strength (MPa) was measured using an Instron testing
machine.
Results: Analysis of variance (ANOVA) was used to evaluate the data. The tensile bond strength were significantly less in experimental
subgroup than control subgroups.
Conclusion: The tensile bond strengths were higher in sound and carious affected dentin without application of caries
detection dyes.
Journal of Conservative Dentistry | Jan-Mar 2011 | Vol 14 | Issue 1

47. IMAGING WITH NEAR-INFRARED LIGHT
• Principle : Enamel is highly transparent in the near infrared (NIR), demineralized areas
appear dark due to attenuation

48. IMAGING WITH NEAR-INFRARED LIGHT
• Advantages:
• Lesion more clearly seen than with bitewing
• Better image contrast at NIR wavelengths than by X rays
• Can differentiate from stains, pigmentation, fluorosis & demineralization
• Can examine defects, cracks in enamel
• Can detect incipient lesions not seen in radiographs

49. IMAGING WITH NEAR-INFRARED LIGHT

50. ENDOSCOPE /VIDEO SCOPE
Consists of a telescope with a camera head, a light source and a monitor for viewing.
• Helps in detecting small carious lesions
• Video camera mounted on custom-made metal mirror holder-
• Image of the enamel surface can be viewed on the screen—videoscope
Advantages :
• Provides a magnified image
• Clinically feasible
Disadvantages :
• Requires drying and isolation of teeth
• Time consuming
• Expensive

51. CONE BEAM CT
• Chief Limitation of conventional intra-oral radiographs is that it produces a 2D image of
a 3D structure.
• CBCT produces three dimensional imaging ( 3D) system
• This method constructs radiographic slices, cross-section through teeth

52. CONE BEAM CT
• CBCT imaging is superior to 2D imaging in the description of
periapical lesions precisely demonstrating lesion
juxtaposition to the maxillary sinus, sinus membrane
involvement and lesion location relative to the mandibular
canal.
• CBCT can be used to
• Determine the number and morphology of roots and
associated canals (both main and accessory)
• Establish working lengths
• Determine the type and degree of root angulation and
as well provides true assessment of present root canal
obturations

53. CONE BEAM CT

54. The Impact of Different Diagnostic Imaging Modalities on the Evaluation of
Root Canal Anatomy and Endodontic Residents’ Stress Levels: A Clinical
Study
Shanon Patel, Risha Patel, Federico Foschi and Franceso Mannocci,
Abstract
Introduction: The purpose of this study was firstly to compare the impact of radiographs, cone-beam computed tomographic
(CBCT) imaging, and 3D Endo software (Dentsply Sirona, Ballaigues, Switzerland) on the assessment of root canal anatomy and
radiographic quality of endodontic treatment and secondly to assess stress levels in the same cohort of residents performing
endodontic treatment.
Methods: Sixty patients requiring primary molar endodontic treatment were allocated randomly into 3 groups: group 1 (n = 20),
conventional radiographs (periapical radiography [PR]) only; group 2 (n = 20), PR and CBCT imaging; and group 3 (n = 20), PR,
CBCT imaging, and 3D Endo software. All treatment was performed using a standardized protocol. Residents completed a
questionnaire to assess their stress levels and usefulness of the imaging modality used. The radiographic quality of completed
cases was assessed by 2 experienced endodontists who were not involved in the supervision of the cases being assessed.
Results: Groups 2 (CBCT imaging) and 3 (PR, CBCT imaging, and 3D Endo) proved significantly better than group 1 (PR) (P < .001)
for assessing the number of root canals and anatomy and estimating the working lengths. Group 3 provided a significantly more
accurate determination of the working level (P = .002). There were significantly more cases with obturation short of the apex (<2
mm) and voids in group 1 compared with group 3 (P < .05) and a significantly higher number of cases with voids in group 1
compared with group 3 (P < .01). Clinicians found treatment to be moderately or very stressful in 75%, 5%, and 0% in groups 1, 2,
and 3, respectively.
Conclusions: 3D Endo software followed by CBCT imaging were found to be more desirable for the evaluation of root canal anatomy
and working lengths and reducing the residents’ stress levels.
Journal of Endodontics 2019

55. • Occlusal and proximal caries : not significantly better than film or digital radiography.
Used in early caries and secondary caries detection
A series of 8–10 radiographic images are exposed at different projection geometries using a
programmable imaging unit, with specialized software to reconstruct a three-dimensional data
set which may be viewed slice by slice.
Advantages of TACT over conventional radiographic techniques is that the images produced have
less superimposition of anatomical noise over the area of interest
TUNED APERTURE COMPUTED TOMOGRAPHY

56. POTENTIAL NEW DIAGNOSTIC MODALITIES
• Multi-photon Imaging
• Infrared Fluorescence
• Optical Coherence Tomography
• Ultrasound
• Tetrahertz Imaging

57. OPTICAL COHERENCE TOMOGRAPHY ( OCT)
• OCT generates high resolution cross-sectional
images of the oral structures
• Uses light for dental imaging; wavelength of 840 to
1320 nm
• OCT is based on interference of two partially
coherent light beams coming from a single source.
• Sound enamel shows high intensity back scattering
at the tooth surface. Incipient lesions shows higher
back scattering indicative of porosity caused by
demineralization.
• Identifies incipient lesions, surface integrity and
lesion depth( J Cant Dent ASSOC, 2008)

58. DIFFERENTIAL DIAGNOSIS
RESTORATIVE MATERIAL ABRASION

59. DIFFERENTIAL DIAGNOSIS
ATTRITION CERVICAL BURNOUT

60. CARIES ACTIVITY
TESTS

61. CARIES ACTIVITY TESTS
DEFINTION OF CARIES ACTIVITY (Messer, Aus Dent J, 2000)
“the rate at which dentition is destroyed by caries, represented by the sum of the new carious
lesions and enlarged lesions per unit time”

62. VARIOUS CARIES ACTIVITY TESTS
• Lactobacillus colony count test
• Snyder test
• Reductase test
• Buffer capacity test
• Fosdick calcium dissolution test
• Dewar test
• Caries risk test

63. LACTOBACILLUS COLONY COUNT TEST
Counts the number of colonies appearing on Tomato Peptone Agar or Rogosa Agar

64. LACTOBACILLUS COLONY COUNT TEST
No of colonies
CFU/ML CARIES ACTIVITY
0-1000 Little or none
1000-5000 Slight
5000-10,000 Moderate
> 10,000 Marked

65. SNYDER TEST
• Principle: Measures the ability of microorganisms in saliva to form acids from
carbohydrate
• Method:
Media contains
• Bactopeptone
• Dextrose
• Sodium chloride
• Agar
• Bromocresol green

66. SNYDER TEST
CARIES ACTIVITY COLOR CHANGE FROM
BLUE/GREEN TO YELLOW
High 24 hrs.
Medium 48 hrs.
Slight 72 hrs.
Immune no change>72 hrs.

67. ALBAN’S TEST
• Modification of Snyder test
• Uses less agar i.e. 5ml per tube
• Saliva is directly drooled into tubes
• Incubated for 4 days at 37deg C
• Color change is noted from bluish green to yellow

68. REDUCTASE TEST
• Sample is mixed with an indicator
i.e. diazoresorcinol
• Changes in color measured after 30
secs & 15 mins
COLOR TIME SCORE CARIES ACTIVITY
Blue 15 min 1 Non conducive
Orchid 15 min 2 Slightly conducive
Red 15 min 3 moderate conducive
Red Immediately 4 Highly conducive
Pink or white Immediately 5 Extremely conducive

69. FOSDICK CALCIUM DISSOLUTION TEST
• 25 ml of gum stimulated saliva is collected
• Placed in an 8 inch test tube with 0.1 gm of powdered human enamel
• Tube shaken for 4 hrs, then again analyzed for calcium content
• The amount of enamel dissolution increases as the caries activity increases

70. CARIES RISK TEST(C.R.T)
• Advocated as a new, quick and effective test
• 2 components
• CRT bacteria
• CRT buffer
• CRT bacteria-estimates the number of cariogenic bacteria in patient’s saliva
• CRT buffer- determines the buffer capacity of saliva

71. CARIES RISK TEST(C.R.T)
• CRT bacteria- two in one dip-in slide test which identifies counts of
• streptococcus mutants
• lactobacillus
• Stimulated saliva is collected and applied to both slides of the dip-in—incubated for 48hrs
at 37°C

72. CARIES RISK TEST(C.R.T)
• CRT buffer- available in the strip form
• Change in color to indicate the buffering capacity-High, Medium, or Low
• Takes 5 minutes

73. CONCLUSION

74. CONCLUSION
Advanced methods for caries diagnosis can be used as adjuncts to the conventional visual and
tactile examination. Most of the advanced methods are not easily available, are time
consuming and needs lot of skill to practice. A combination of these newer techniques with the
conventional methods would help us to give more reliable and accurate results.

75. THANK YOU!