CARIES CARIES DIAGNOSISDIAGNOSIS

What is diagnosis?What is diagnosis?Diagnosis is an art and science that results from the synthesis of scientific knowledge, clinical experience, intuition & common sense

Caries diagnosis implies deciding whether a lesion is active, progressing rapidly or slowly or whether is already arrested.

ASSESSMENT TOOLSASSESSMENT TOOLSStepwise progression toward diagnosis Stepwise progression toward diagnosis

& treatment planning depends on & treatment planning depends on thorough assessment of the followingthorough assessment of the following

Patient HistoryPatient History Clinical examinationClinical examination Nutritional analysisNutritional analysis Salivary analysisSalivary analysis Radiographic assessmentRadiographic assessment

HIGH RISKHIGH RISK LOW RISKLOW RISKSocial HistorySocial History

Socially deprivedSocially deprivedHigh caries in siblingsHigh caries in siblingsLow knowledge of cariesLow knowledge of caries

Middle class Middle class Low caries in siblingLow caries in siblingHigh dental aspirationsHigh dental aspirations

Medical HistoryMedical HistoryMedically compromisedMedically compromisedXerostomiaXerostomiaLong-term cariogenic Long-term cariogenic medicinemedicine

No such problemNo such problem

Dietary habitsDietary habits

Sugar intake: frequentSugar intake: frequent Infrequent Infrequent

HIGH RISKHIGH RISK LOW RISKLOW RISKUse of fluorideUse of fluoride

Non-fluoridated areaNon-fluoridated areaNo fluoride supplementsNo fluoride supplements

Fluoridated areaFluoridated areaFluoride supplements usedFluoride supplements used

Plaque controlPlaque controlPoor oral hygiene Poor oral hygiene maintenancemaintenance

Good oral hygiene Good oral hygiene maintenancemaintenance

SalivaSaliva

Low flow rate& buffering Low flow rate& buffering capacitycapacity S.mutans & lactobacillus S.mutans & lactobacillus countscounts

Normal flow rate& buffering Normal flow rate& buffering capacity capacity S.mutans & lactobacillus S.mutans & lactobacillus countscounts

HIGH RISKHIGH RISK LOW RISKLOW RISKClinical evidenceClinical evidence

New lesionsNew lesionsPremature extractionsPremature extractionsAnterior caries restorationsAnterior caries restorationsMultiple/repeated Multiple/repeated restorationsrestorationsNo fissure sealantsNo fissure sealantsMulti-band orthodonticsMulti-band orthodontics

No new lesionsNo new lesionsNo extraction for cariesNo extraction for cariesSound anterior teethSound anterior teethNo/few restorationsNo/few restorations

Fissure sealedFissure sealedNo appliancesNo appliances

CONVENTIONAL METHODS CONVENTIONAL METHODS OF CARIES DETECTIONOF CARIES DETECTION

VISUAL-TACTILE METHODVISUAL-TACTILE METHOD RADIOGRAPHYRADIOGRAPHY CARIES DETECTING DYESCARIES DETECTING DYES FIBEROPTIC TRANSILLUMINATIONFIBEROPTIC TRANSILLUMINATION ELECTRONIC CARIES MONITORELECTRONIC CARIES MONITOR

VISUAL-TACTILE METHODSVISUAL-TACTILE METHODSVisual methods:Visual methods: Detection of white spot, discoloration / frank cavitationsDetection of white spot, discoloration / frank cavitations Without aids, unreliableWithout aids, unreliable Magnification loupes- Head worn prism loupes (X 4.5) or Magnification loupes- Head worn prism loupes (X 4.5) or

surgical microscopes(X 16) may be usedsurgical microscopes(X 16) may be usedcomfort, relatively inexpensive, available in comfort, relatively inexpensive, available in

various various magnificationmagnification Use of temporary elective tooth separationUse of temporary elective tooth separation

Tactile methods:Tactile methods:

Explorers are widely used for the detection of carious Explorers are widely used for the detection of carious tooth structuretooth structure

- Right angled probe- no.6- Right angled probe- no.6- Back action probe- no.17- Back action probe- no.17- Shepherd's crook- no. 23- Shepherd's crook- no. 23- Cowhorn with curved ends- no.2- Cowhorn with curved ends- no.2

Dental flossDental floss

Use of explorer is not advocated Use of explorer is not advocated because;because;

Sharp tips physically damage small Sharp tips physically damage small lesions with intact surfaceslesions with intact surfaces

Probing can cause fracture & cavitation of Probing can cause fracture & cavitation of incipient lesion. It may spread the incipient lesion. It may spread the organism in the mouthorganism in the mouth

Mechanical binding may be due to non-Mechanical binding may be due to non-carious reasonscarious reasons

Shape of fissureShape of fissureSharpness of explorer Sharpness of explorer Force of applicationForce of applicationPath of explorer placementPath of explorer placement

Use of explorer Use of explorer • Explorer is useful to remove plaque Explorer is useful to remove plaque

and debris and check the surface and debris and check the surface characteristics of suspected carious characteristics of suspected carious lesions.lesions.

• gentle pressure just required to blanch gentle pressure just required to blanch a fingernail without causing any pain a fingernail without causing any pain or damageor damage

• All surfaces of a tooth are cleaned of All surfaces of a tooth are cleaned of debris and plaque, using an air debris and plaque, using an air syringe and examined visually. syringe and examined visually. Suspicious areas are explored to Suspicious areas are explored to check for the surface texture.check for the surface texture.

SMOOTH SURFACE CARIESSMOOTH SURFACE CARIESNon- cavitated:Non- cavitated: No signs of cavitation after visual or No signs of cavitation after visual or

tactile examination. tactile examination. Location: where dental plaque Location: where dental plaque

accumulates (gingival margin).accumulates (gingival margin). Surface characteristics: Matted (not Surface characteristics: Matted (not

glossy) when a tooth is dried. glossy) when a tooth is dried.

Areas of demineralization Areas of demineralization not in close proximity to the gingival not in close proximity to the gingival

marginmarginnot covered by plaquenot covered by plaquesmooth and glossysmooth and glossyare non-cavitated are non-cavitated

not active non-cavitated carious lesionsnot active non-cavitated carious lesions.. Visual enamel opacity under sound Visual enamel opacity under sound

marginal ridge indicate undermined marginal ridge indicate undermined enamel due to dental caries enamel due to dental caries

non-cavitated carious lesion in dentinnon-cavitated carious lesion in dentin

Non-cavitated carious lesionENAMEL DENTIN

Cavitated Lesions:Cavitated Lesions: Where there is visual breakdown of a tooth Where there is visual breakdown of a tooth

surface, it is classified as cavitated carious surface, it is classified as cavitated carious lesion. An active cavity on a smooth lesion. An active cavity on a smooth surface has soft walls or floors shown surface has soft walls or floors shown below:below:

Questionable Area:Questionable Area: All stained smooth coronal tooth surfaces All stained smooth coronal tooth surfaces

that do not have the characteristics of that do not have the characteristics of non-cavitated or cavitated lesions are non-cavitated or cavitated lesions are classified as questionable shown belowclassified as questionable shown below

Non-Carious Enamel OpacitiesNon-Carious Enamel Opacities

Opacity not fluorosis

Mild Fluorosis

Moderate Fluorosis

Severe Fluorosis

Caries in Pit or Fissure SurfacesCaries in Pit or Fissure Surfaces All discolored areas should be explored using gentle All discolored areas should be explored using gentle

pressure. pressure. There is no need to penetrate a suspected lesion There is no need to penetrate a suspected lesion

with an explorer.with an explorer. If a discolored and non-cavitated area is soft when If a discolored and non-cavitated area is soft when

explored, it is recorded as explored, it is recorded as non-cavitated carious pit non-cavitated carious pit or fissureor fissure..

A A cavitycavity is detected when there is an actual hole in is detected when there is an actual hole in the tooth in which an explorer could easily enter the the tooth in which an explorer could easily enter the space.space.

An active cavity has soft walls or floors (detected An active cavity has soft walls or floors (detected using gentle exploring).using gentle exploring).

If there is visual enamel opacity under an If there is visual enamel opacity under an ostensibly sound or stained pit or fissure, ostensibly sound or stained pit or fissure, then the enamel is undermined because of then the enamel is undermined because of dental caries and the tooth surface is dental caries and the tooth surface is classified withclassified with a non-cavitated carious a non-cavitated carious lesion in dentinlesion in dentin..

Pit and Fissure CariesPit and Fissure CariesNon-cavitated carious lesion

Enamel

Enamel

Dentin

Enamel

If a discolored area is hard when gently If a discolored area is hard when gently explored then it should be marked as explored then it should be marked as questionablequestionable..

Cavitated Carious lesion

Root CariesRoot Caries • Root surface caries comprises of a Root surface caries comprises of a

continuum of changes ranging from continuum of changes ranging from minute discolored areas to cavitation that minute discolored areas to cavitation that may extend into the pulpmay extend into the pulp

For diagnostic purpose; they may be:For diagnostic purpose; they may be: Active root surface lesion:Active root surface lesion:

• well-defined area showing yellowish or light well-defined area showing yellowish or light brown discolorationbrown discoloration

• covered by visible plaquecovered by visible plaque• presence of softening/ leathery consistency on presence of softening/ leathery consistency on

probing with moderate pressureprobing with moderate pressure

Inactive root surface lesion (arrested):Inactive root surface lesion (arrested):• well-defined dark brown/ black discolorationwell-defined dark brown/ black discoloration

• smooth and shinysmooth and shiny• hard on probing with moderate pressurehard on probing with moderate pressureActive lesion

Questionable

Arrested CariesArrested Caries Arrested (remineralized) lesions can

be observed clinically as intact, but discolored, usually brown or black spots.

The change in color is presumably due to trapped organic debris and metallic ions within the enamel.

These discolored, remineralized lesions are intact and are highly resistant to subsequent caries . The arrested caries need not be removed.

Recurrent caries Recurrent caries It is diagnosed whenever there is softness due It is diagnosed whenever there is softness due

to caries at a defective margin, and when the tip to caries at a defective margin, and when the tip of a periodontal probe can enter the defect of a periodontal probe can enter the defect without any resistance.without any resistance.

A restoration with a discolored margin or a small A restoration with a discolored margin or a small marginal ditch (<0.5 mm or the head of the marginal ditch (<0.5 mm or the head of the probe) is recorded as anprobe) is recorded as an early recurrent early recurrent carious areacarious area. A larger defect should be . A larger defect should be classified as classified as advanced recurrent carious areaadvanced recurrent carious area

There are two valid indicators of recurrent There are two valid indicators of recurrent (secondary) caries: (secondary) caries:

• softness at the margin of a filling that is detected softness at the margin of a filling that is detected using an explorer or using an explorer or

• presence of a large defect (a minimum diameter of presence of a large defect (a minimum diameter of 0.4 mm) at a margin of a filling with softness in the 0.4 mm) at a margin of a filling with softness in the area. area.

Large defects are associated with a high level of Large defects are associated with a high level of colonization with cariogenic bacteria. Marginal colonization with cariogenic bacteria. Marginal discoloration by itself is not a valid sign for discoloration by itself is not a valid sign for dental caries.dental caries.

Advanced Recurrent Carious lesions

Nursing bottle caries Vs Rampant cariesNursing bottle caries Vs Rampant caries

Specific form of rampant cariesSpecific form of rampant caries Acute, widespread caries with Acute, widespread caries with early pulpal involvement of early pulpal involvement of teeth that are usually immune to teeth that are usually immune to decaydecay

Primary dentition affectedPrimary dentition affected Both dentitions affectedBoth dentitions affected

C/F: specific pattern- maxillary C/F: specific pattern- maxillary incisor incisor molarsmolarsMandibular incisors not affectedMandibular incisors not affected

Rapid appearance of new lesionsRapid appearance of new lesionsMandibular incisors also Mandibular incisors also affectedaffected

RADIOGRAPHYRADIOGRAPHY Carious lesions are detectable radiographically Carious lesions are detectable radiographically

when there has been enough demineralization to when there has been enough demineralization to allow it to be differentiate from normalallow it to be differentiate from normal

They are valuable in detecting proximal caries They are valuable in detecting proximal caries which may go undetected during clinical which may go undetected during clinical examination.examination.

On average they have around 50% to 70% On average they have around 50% to 70% sensitivity in detecting carious lesions.sensitivity in detecting carious lesions.

40% demineralization is required for definitive 40% demineralization is required for definitive decision on cariesdecision on caries

Radiographic examinations include;Radiographic examinations include;Bitewing radiographsBitewing radiographsIOPA radiographs using paralleling IOPA radiographs using paralleling

techniquetechniqueDental panoramic tomographDental panoramic tomograph

The two important decisions related to The two important decisions related to radiographic examination are (1) when to take a radiographic examination are (1) when to take a radiograph and (2) how to evaluate a radiograph radiograph and (2) how to evaluate a radiograph for presence of signs of dental caries. for presence of signs of dental caries.

Incipient occlusal lesions:Not very effective.Not very effective.Caries starts on the walls Caries starts on the walls of the pits & fissures and of the pits & fissures and tends to spread tends to spread perpendicular to the DEJperpendicular to the DEJOnly detectable change is Only detectable change is a fine gray shadow at the a fine gray shadow at the DEJ.DEJ.

PIT & FISSURE PIT & FISSURE CARIESCARIES

Moderate occlusal lesions:Moderate occlusal lesions:First to induce specific changes First to induce specific changes helping in a definitive diagnosishelping in a definitive diagnosisBroad based, thin radiolucent Broad based, thin radiolucent zone in dentin with minimal or zone in dentin with minimal or no changes in enamelno changes in enamelPresence of a band of increased Presence of a band of increased opacity between the lesion and opacity between the lesion and the pulp chamber due to the pulp chamber due to calcification within primary calcification within primary dentindentinThis feature is not seen in This feature is not seen in buccal cariesbuccal caries

Severe occlusal Severe occlusal lesions:lesions:Readily observed both Readily observed both clinically and clinically and radiographicallyradiographicallyAppear as large cavities in Appear as large cavities in the crowns of the teeththe crowns of the teethHowever pulp exposure However pulp exposure cannot be determinedcannot be determined

PROXIMAL CARIESPROXIMAL CARIES

Incipient lesions:Incipient lesions:Commonly seen in the caries-Commonly seen in the caries-susceptible zone susceptible zone Presents as a notch on the outer Presents as a notch on the outer surface not involving more than half surface not involving more than half of enamelof enamelDiagnosis can be missed, best Diagnosis can be missed, best viewed under a magnifying glass.viewed under a magnifying glass.

Density along the proximal surface is high which does not permit the detection of loss of small amounts of mineral content

Moderate proximal lesions:Moderate proximal lesions:Involve more than outer half of Involve more than outer half of enamel but do not extend into enamel but do not extend into DEJDEJMay have one of type of May have one of type of appearance:appearance:67%67% - triangle with broad base - triangle with broad base towards outer towards outer surfacesurface16%16% - a diffuse radiolucent - a diffuse radiolucent imageimage17%17% - combination of both - combination of both

Advanced proximal Advanced proximal lesions:lesions:Radiolucent triangular cone Radiolucent triangular cone invading into the dentininvading into the dentinIn addition, it spreads along In addition, it spreads along the DEJ and subsequently into the DEJ and subsequently into dentindentinThis forms a 2This forms a 2ndnd cone with cone with base at DEJbase at DEJDoes not involve more than Does not involve more than half of dentinhalf of dentinIn some cases, lesions In some cases, lesions penetrated into dentin may penetrated into dentin may appear not to have penetrated appear not to have penetrated enamelenamel

Severe proximal lesions:Severe proximal lesions:Penetrating more than half Penetrating more than half of dentinof dentinNarrow path through Narrow path through enamel, an expanded enamel, an expanded radiolucency at DEJ, with a radiolucency at DEJ, with a progress towards pulpprogress towards pulpLesions may or may not Lesions may or may not appear to involve pulpappear to involve pulpUndermined enamel Undermined enamel fractures under masticatory fractures under masticatory load leaving a large cavityload leaving a large cavity

Facial & Lingual CariesFacial & Lingual Caries They start as round lesions and They start as round lesions and

enlarge to become elliptical or enlarge to become elliptical or semilunarsemilunar

Presence of well defined non-Presence of well defined non-carious enamel around carious enamel around radiolucencyradiolucency

When superimposed on DEJ, When superimposed on DEJ, they may mimic occlusal cariesthey may mimic occlusal caries

Clinical examination helps in Clinical examination helps in definitive diagnosis definitive diagnosis

ROOT SURFACE CARIESROOT SURFACE CARIES

Also called cemental caries Also called cemental caries with an incidence of 40%- 70% with an incidence of 40%- 70% of the aged populationof the aged population

Buccal, lingual, proximalBuccal, lingual, proximal Usually it is a lesion of dentin Usually it is a lesion of dentin

associated with recessionassociated with recession Ill-defined, saucer-like Ill-defined, saucer-like

radiolucencyradiolucency

RECURRENT CARIESRECURRENT CARIES Occurs immediately next to Occurs immediately next to

restorationsrestorations Results from microleakage or residual Results from microleakage or residual

cariescaries Incidence- 16%Incidence- 16%

Radiolucency depends on amount of demineralization Radiolucency depends on amount of demineralization & extent of restoration& extent of restorationMesio/disto-gingival & occlusal margins- clearly seenMesio/disto-gingival & occlusal margins- clearly seenUnder facial/ lingual restorations-difficult to detectUnder facial/ lingual restorations-difficult to detectMaterials like Ca(OH),composite & silicate cementsMaterials like Ca(OH),composite & silicate cements

OTHER RADIOGRAPHIC OTHER RADIOGRAPHIC SHADOWSSHADOWS

Radiolucent Radiolucent Cervical Burn out:Cervical Burn out:- - Evident at the neck of tooth well Evident at the neck of tooth well demarcated above by enamel demarcated above by enamel cap& below by alveolar bone cap& below by alveolar bone levellevel- It is triangular in shape being - It is triangular in shape being less apparent at the center of toothless apparent at the center of tooth--good alveolar bone height will good alveolar bone height will enhance cervical burn-outenhance cervical burn-out

Radiopaque zone beneath amalgam restorationsTin & zinc ions are released into underlying dentin

Pitfalls Of RadiographyPitfalls Of Radiography 2 dimensional view of 3 dimensional object2 dimensional view of 3 dimensional object Radiographic depth of a lesion is often less than Radiographic depth of a lesion is often less than

actual depthactual depth Overlapping of proximal surfaces on a Overlapping of proximal surfaces on a

radiograph radiograph Occlusal (incipient) caries of enamel difficult to Occlusal (incipient) caries of enamel difficult to

detectdetect Dental anomalies like hypoplastic pits mimic Dental anomalies like hypoplastic pits mimic

proximal cariesproximal caries Cervical burnout often confused with root cariesCervical burnout often confused with root caries

XERORADIOGRAPHYXERORADIOGRAPHY It is similar to photocopy machine Consists of Aluminum plate coated with selenium which

provides a uniform electrostatic charge X- rays selective discharge of particles Latent

image Processing unit: Latent image positive image Very good Edge enhancement i.e., differentiating areas

with different densities Twice more sensitive than D speed film, but equivalent

to E speed film Disadvantages:

Electrostatic charge may cause patient discomfortProcessing to be completed by 15 minutes

DIGITAL IMAGINGDIGITAL IMAGING A digital image is an image formed & represented by a

spatially distributed set of discrete sensors & pixels 2 types of non- film receptors

Direct digital imaging – digital image receptorIndirect digital imaging – video camera for forming

digital images of a radiograph Two types of detectors are used in Direct digital imaging

Photostimulable phosphor ( PSP) –barium

fluorohalideCharged couple device (CCD) – silicon

Image is stored on a computer

DIGITAL IMAGINGDIGITAL IMAGING

Schick System Digora System Trophy System

Manipulation of images1. Magnification 2.Variable contrast 3. variable density 4. Labeling important information 5. Highlighting and colorization Advantages: 1.Images are available in seconds 2. Exposure is reduced 50-90% 3. Image size, contrast and density can be manipulated to

improve interpretation 4. Record keeping is vastly improved. All films are labeled,

filed and retrieved easily. Duplicate hard copies are the same as originals and simple to make

5. Provision of teletransmission

SUBTRACTION RADIOGRAPHYSUBTRACTION RADIOGRAPHY Structured noise is reduced in order to increase the

detectablity of changes in the radiograph Structured noise refers to the information on the

radiograph which have not diagnostic value It requires 2 identical images. The subtracted image is a

composite these two, representing a difference in their densities

Sensitive enough to detect changes of 0.12 mm 90% accurate in detecting mineral loss of 5% Black end of gray scale suitable for proximal & recurrent

caries Contrast can be enhanced with color aid.

COMPUTER IMAGE ANALYSISCOMPUTER IMAGE ANALYSIS Softwares have been developed for automated

procedures which are able to overcome the short coming of human eye

Software supports an operation whereby a threshold is set up by the examiner which determines the program’s display of lesion probability

Tuned Aperture Computed Tomography (TACT) involve the tomosynthesis of structures in 3D thereby increasing the accurate detection of caries

Useful for monitoring carious lesion Increased sensitivity but decreased specificity

DYES FOR CARIES DYES FOR CARIES DETECTIONDETECTION

They selectively complex with carious tooth structure which is later disclosed with the help of fluorescence

Aids in both quantitative & qualitative analysis of the lesionDYES FOR ENAMEL CARIES:

Procion: N2 & (OH) groups irreversibly complex with caries Acts as a fixativeCalcein: complexes with calcium & remains bound to the toothZyglo ZL-22: fluorescent tracer dye, not used in vivoBrilliant blue: 10% aqueous Brilliant Blue, not used in vivo

DYES FOR DENTIN CARIES: 1% acid red 52 in propylene glycol complexes specifically

with denatured collagen, hence used to differentiate infected and affected dentin

Iodine penetration method (Pot iodide) for evaluating enamel permeability

DISADVANTAGES• Dye staining and bacterial penetration are independent

phenomena, hence no actual quantification• They also stain food debris, enamel pellicle, other organic

matter• Dye aided carious removal- laborious • Stains DEJ

FIBEROPTIC FIBEROPTIC TRANSILLUMINATIONTRANSILLUMINATION

Different index of light transmission for decayed & sound tooth. Decayed tooth structure has decreased index & appears dark

The tooth is illuminated using fiberoptics Have a high level intra & inter-examiner

variability Digital imaging FOTI introduced, images

captured by a CCD camera & fed into the computer for image analysis

DIFOTI can detect caries on all types of teeth & also detect incipient & recurrent caries before their visibility on radiographs

ELECTRIC MEASUREMENTS FOR ELECTRIC MEASUREMENTS FOR CARIESCARIES

First proposed by Magitot in 1878 Tooth demineralization due to caries

process causes increased porosity of tooth structure. This porosity contains fluid containing ions. This leads increased electrical conductivity, conversely, leads to decreased electrical resistance or impedance

ECM device uses a fixed-frequency (23 Hz)alternating current which measures ‘bulk resistance’ of tooth

Two systemsVangaurd system – 25 Hz – ordinal scale of 0 –9Caries meter L – 400 Hz – 4 colored lightsgreen –no caries yellow – enamel cariesorange – dentin caries red –pulp involvement

ECM limited to occlusal sites.ECM to H/P- 97% accuracy Cannot be used where amalgam filling is present Materials have different responses at different

frequencies. Electrical Impedance Spectroscopy (EIS) operates over different frequencies & thus determine more accurately these differences. EIS can be used on both occlusal & proximal surfaces

Factors affecting electrical measurements1. Porosity2. Surface area3. Thickness of the tissues4. Hydration of enamel5. Temperature6. Concentrations of ions in the dental tissue

fluids

RECENT ADVANCES IN RECENT ADVANCES IN CARIES DETECTIONCARIES DETECTION

Research in the past two decades has lead to the development of new technologies that asses changes in fluorescence of enamel & dentin due to loss of mineral

Benedict- 1929, normal teeth fluorescence Optical methods used are

Quantitative light- induced fluorescence- QLF™ Infrared laser fluorescence - DIAGNOdent

CARIES RISK CARIES RISK ASSESSMENTASSESSMENT

Clinical examination neither predicts caries Clinical examination neither predicts caries activity nor susceptibilityactivity nor susceptibility

Certain simple reliable lab tests can Certain simple reliable lab tests can facilitate this,which is important because;facilitate this,which is important because;- need & extent of personalized preventive - need & extent of personalized preventive measures measures - index for therapeutic measures- index for therapeutic measures- patient education- patient education- manage progress of restorative - manage progress of restorative proceduresprocedures- identify high risk groups / individuals- identify high risk groups / individuals

Requisites of testsRequisites of tests Correlation between predicted & actual Correlation between predicted & actual

caries developmentcaries development Reliability & validityReliability & validity Simple to performSimple to perform Quick resultsQuick results Measurement of mechanism involved Measurement of mechanism involved

in caries processin caries process

Caries activity Vs Caries susceptibilityCaries activity Vs Caries susceptibility Caries activity refers to the increment Caries activity refers to the increment

of active lesionsof active lesions Susceptibility refers to inherent Susceptibility refers to inherent

propensity of the host & target tissue propensity of the host & target tissue affected by cariesaffected by caries

Most of the tests measures the formerMost of the tests measures the former Caries activity tests measure either the Caries activity tests measure either the

quantity of specific bacterial group or quantity of specific bacterial group or their ability to produce acids. Hence their ability to produce acids. Hence this must be coupled with clinical this must be coupled with clinical examination prior to treatment examination prior to treatment planning.planning.

Caries Activity TestsCaries Activity TestsLactobacillus colony count test:Lactobacillus colony count test: Introduced by Hadley in 1933Introduced by Hadley in 1933 Stimulated saliva collected & diluted with distilled Stimulated saliva collected & diluted with distilled

water. Spread evenly on Rogasa’s SL agar plate. water. Spread evenly on Rogasa’s SL agar plate. Incubated at 37Incubated at 37C for 3-4 days. No.of colonies C for 3-4 days. No.of colonies developed counteddeveloped counted

No.of org/ mlNo.of org/ ml Degree of caries Degree of caries activityactivity

0 – 10000 – 1000 Little / noneLittle / none1000 – 50001000 – 5000 SlightSlight

5000 – 10,0005000 – 10,000 ModerateModerate> 10,000> 10,000 markedmarked

Calorimetric Snyder test:Calorimetric Snyder test: Measures the ability of micro organisms to form Measures the ability of micro organisms to form

organic acids in carbohydrateorganic acids in carbohydrate 0.2 ml of patient’s saliva is pipetted into melted 0.2 ml of patient’s saliva is pipetted into melted

medium at 50medium at 50C. Incubated for 72 hrs. medium C. Incubated for 72 hrs. medium contains bromocresol green which changes color contains bromocresol green which changes color from green to yellow in the range of pH5.4 – 3.8from green to yellow in the range of pH5.4 – 3.8

If yellowIf yellowMarked caries Marked caries activityactivity

If yellowIf yellowDefinite caries Definite caries activityactivity

If yellowIf yellowLimited caries Limited caries activityactivity

If greenIf greenObserve – 48hrsObserve – 48hrs

If greenIf greenObserve –72hrsObserve –72hrs

If greenIf greenCaries inactiveCaries inactive

24 hrs 48 hrs 72 hrs

Swab Test:Swab Test: Developed by Grainger in 1965Developed by Grainger in 1965 Based on the principle of Snyder testBased on the principle of Snyder test Swab is taken from the teeth & incubated in Swab is taken from the teeth & incubated in

mediummedium pH change after 48 hrs is read on a pH meterpH change after 48 hrs is read on a pH meter

pH 4.1or lesspH 4.1or less Marked caries Marked caries activityactivity

pH 4.2 – 4.4pH 4.2 – 4.4 ActiveActive

pH 4.5 – 4.6pH 4.5 – 4.6 Slightly activeSlightly activepH 4.6 0r morepH 4.6 0r more Caries inactiveCaries inactive

Salivary buffer capacity:Salivary buffer capacity: Tests the buffering capacity of bicarbonate ion in Tests the buffering capacity of bicarbonate ion in

salivasaliva 2 ml of stimulated saliva + 4 ml of distilled water2 ml of stimulated saliva + 4 ml of distilled water Set up is placed under paraffin seal to prevent loss Set up is placed under paraffin seal to prevent loss

of volatile bicarbonate ionof volatile bicarbonate ion Micro-burette & micro glass electrode are Micro-burette & micro glass electrode are

introduced under the seal & the amount of 0.5 N introduced under the seal & the amount of 0.5 N HCl required to bring saliva to pH 5 is measured HCl required to bring saliva to pH 5 is measured

Samples requiring less than 0.45 ml of HClSamples requiring less than 0.45 ml of HCl indicate low buffering capacity & vice-versaindicate low buffering capacity & vice-versa

Saliva-Check BUFFER:Saliva-Check BUFFER: Checking pH level & salivary buffering capacity of Checking pH level & salivary buffering capacity of

resting & stimulated salivaresting & stimulated saliva The kit consists of pH strips 5.0 – 8.0 & buffering The kit consists of pH strips 5.0 – 8.0 & buffering

stripsstrips Resting salivary analysis is made by asking the Resting salivary analysis is made by asking the

patient to expectorate any pooled salivapatient to expectorate any pooled saliva Stimulated saliva is obtained by asking the patient Stimulated saliva is obtained by asking the patient

to chew paraffin wax for 30 secto chew paraffin wax for 30 sec Samples collected are tested with the strips Samples collected are tested with the strips

available in the kitavailable in the kit Buffer strips contain 3 rows test pads. Salivary Buffer strips contain 3 rows test pads. Salivary

sample is pipetted onto each of these pads. Color sample is pipetted onto each of these pads. Color change noted after 5 minchange noted after 5 min

pH analysis:pH analysis: Results in 10 secondsResults in 10 seconds

Color changeColor change pH rangepH rangeRedRed 5.0 – 5.85.0 – 5.8

Yellow Yellow 6.0 – 6.66.0 – 6.6GreenGreen 6.8 – 7.86.8 – 7.8

Buffering capacity analysis: Results 5 min

Color change on each of the test pad is noted & points are assigned accordingly

Green – 4 pts Blue/ Red – 1 pt

Green/ blue – 3 pts Red – 0 pt

Blue – 2 pts

Interpreting results:Interpreting results:

Combined totalCombined total Buffering abilityBuffering ability

0 – 50 – 5 Very lowVery low

6 – 96 – 9 LowLow

10 – 1210 – 12 Normal/ highNormal/ high

Alban test:Alban test: Simplified substitute of Snyder testSimplified substitute of Snyder test Alban test medium – 60 g Snyder test agar + 1 liter Alban test medium – 60 g Snyder test agar + 1 liter

waterwater Patient to expectorate saliva in test tube containing Patient to expectorate saliva in test tube containing

Alban test medium. Incubated at 37Alban test medium. Incubated at 37C upto 4 daysC upto 4 days Tubes are observed daily for:Tubes are observed daily for:

- change of colour from green to yellow- change of colour from green to yellow- depth in the medium to which change has - depth in the medium to which change has occurredoccurred

Scale for scoring:Scale for scoring:color change is noted After 72 hrs/ 96 hrs of color change is noted After 72 hrs/ 96 hrs of

incubationincubation1.1. No color changeNo color change2.2. Beginning of color change = +Beginning of color change = +

(from top to bottom)(from top to bottom)

3.3. One half color change = ++One half color change = ++4.4. ¾ color change = +++¾ color change = +++5.5. Total color change = ++++Total color change = ++++

Caries Susceptibility TestCaries Susceptibility TestEnamel solubility test:Enamel solubility test: When glucose is added to saliva containing When glucose is added to saliva containing

powdered enamel, organic acids are formed. This will powdered enamel, organic acids are formed. This will decalcify enamel leading to an increase in soluble Ca decalcify enamel leading to an increase in soluble Ca ionsions

Amount of Ca obtained gives a direct measure of Amount of Ca obtained gives a direct measure of caries susceptibilitycaries susceptibility

Salivary reductase test:Salivary reductase test: Measures the activity of reductase enzyme in salivary Measures the activity of reductase enzyme in salivary

bacteriabacteria Kit commercially available- TreatexKit commercially available- Treatex Salivary sample mixed with Diazoresorcinol dyeSalivary sample mixed with Diazoresorcinol dye

Color changes are tabulated after 15 minColor changes are tabulated after 15 min

ColorColor Caries Caries conducivenessconduciveness

Blue in 15 minBlue in 15 min Non- ConduciveNon- ConduciveOrchid in15 minOrchid in15 min Slightly ConduciveSlightly ConduciveRed in 15 minRed in 15 min Moderately Moderately

ConduciveConduciveRed immediately Red immediately on mixingon mixing

Highly ConduciveHighly Conducive

Colorless in 15 Colorless in 15 minmin

Extremely Extremely ConduciveConducive

CARIOGRAMCARIOGRAM Introduced by Bratthall to assess factors contributing Introduced by Bratthall to assess factors contributing

to development of cariesto development of caries Consists of a pie diagram divided into 5 sectorConsists of a pie diagram divided into 5 sector

-- Green Green – estimation of the chance to avoid caries – estimation of the chance to avoid caries- - Dark blueDark blue – Diet – Diet- - RedRed – bacteria- amt of plaque & S. mutans – bacteria- amt of plaque & S. mutans- - Light BlueLight Blue – Susceptibility- combination of F – Susceptibility- combination of F

program Saliva secretion & buffering program Saliva secretion & buffering capacitycapacity

- - YellowYellow – Circumstances- past caries experience & – Circumstances- past caries experience & related diseaserelated disease