2. Tests for prediction and Activity of dental caries
Presented by :
Deepti Awasthi

3. CONTENTS Introduction Definition Objectives Uses for Clinician
Ideal requisites of caries activity test
Tests
Conclusion
References

4. INTRODUCTION

5. DEFINITIONS Caries activity Caries susceptibility
Caries activity tests

6. Objectives Identify high risk group and individual
Determine need for preventive measures
To serve as an index of the success of the therapeutic measures.
To motivate and to monitor the effectiveness of education programs
Manage the progress of restorative procedures.

7. Uses for Clinician Determine need for caries control measure
Indicator of patient co-operation
Aid in timing of recall appointments
Guide to insertion of expensive restorations
Determine the prognosis
Precautionary signal to the orthodontist in placing bands

8. IDEAL REQUISITES Sound theoretical basis
Maximum correlation with clinical status.
Accurate with respect to duplication of results.
Simple
Quick in performance
Inexpensive , feasible
Validity
Reliability
Sensitivity
Specificity

9. Various caries activity tests

10. 1. LACTOBACILLUS COLONY COUNT TEST
introduced by HADLEY in 1933
Principle
This test measures the number of acidogenic and aciduric bacteria in patient’s saliva by counting the number of colonies on tomato peptone agar plates after inoculation with a sample of saliva.
Cariology , 3rd Ed. - Earnest Newbrun

11. Procedure
patient chews a small piece of paraffin
before breakfast
The saliva that accumulates in the 3 minute period is collected in a sterile container
Saliva collected is shaken by a machine for 2 minutes

12. 0.4 ml of each sample is spread on the surface of an agar plate
The saliva sample is diluted with sterile saline solution to 1:100
0.4 ml of each sample is spread on the surface of an agar plate
The plates are incubated for 3 to 4 days at 37°C
The number of Lactobacillus colonies that develop are counted using Quebec counter.

13. Interpretation of LB colony count test
No. of organism
CFU/ml
Symbolic designation
Degree of caries activity +
Little or No
Slight ++
1,000– 5000
Moderate
+++
,000
Marked
++++
> 10,000

14. Disadvantages Quick and easy but results are available in days.
Counting colony tedious
complex instrument, trained personnel required
Not completely exclude the growth of other relatively aciduric organisms
Inaccurate for predicting the onset of caries

15. 2. Colorimetric SNYDER TEST
SNYDER in 1951
Principle
Test measures the ability of salivary microorganisms to form organic acid from a carbohydrate medium
Bromocresol green indicator dye, changes colour from green to yellow at pH 5.4 to 3.8
Essentials of Preventive and community Dentistry- Soben Peter

16. Procedure
Salivary sample is collected after the patient chews a small piece of paraffin before breakfast.
0.2 cc of saliva is pipetted into the 10ml melted agar containing medium in a test tube at 50°C, allowed to solidify and then incubated at 37°C .
The incubation period is upto 72 hours.

17. . The media contains : Bactopeptone Dextrose Sodium chloride Agar
Bromocresol green
The rate of colour change from green to yellow is indicative of the degree of caries activity. .

18. INTERPRETATION TIME 24 hrs 48 hrs 72 hrs COLOUR YELLOW CARIES ACTIVITY
MARKED
DEFINITE
LIMITED
GREEN
CONTINUE TEST
INACTIVE

19. Advantages :
relatively simple
Moderate cost
Disadvantages :
Time consuming
Sometimes color change is not very clear
Limited predictive value

20. 3. THE SWAB TEST GRAINGER et al in 1965. Principle
same as Synder test.
Cariology , 3rd Ed. - Earnest Newbrun

21. Procedure
The oral flora is sampled by swabbing the buccal surfaces of the teeth with a cotton applicator,
subsequently incubated in the medium.
The change in the pH following a 48 hour incubation is read on a pH meter or the colour change is read by the use of a colour comparator.

22. Interpretation :
pH 4.1 and < 4.1 = Marked caries
pH 4.2 to = Active
pH 4.5 to 4.6 = Slightly active
pH 4.6 and over = Caries inactive

23. 4. SALIVARY REDUCTASE TEST
measures the activity of the reductase enzyme present in salivary bacteria
This enzyme is involved in the reactions for the formation of products dangerous to the tooth surface.
Rate at which the indicator molecule , diazoresorcinol, changes from blue to red to colorless

24. Procedure
Saliva is collected by chewing a special flavoured paraffin and expectorated directly into collection tubes
The sample is then mixed with the dye Diazo-resorcinol
The colour changes and the “Caries Conduciveness” reading is taken after 15 minutes

25. COLOUR CHANGES COLOUR CARIES CONDUCIVENESS Blue 15 minutes
Non – Conducive (1)
Orchid minutes
Slightly Conducive (2)
Red minutes
Moderately Conducive (3)
Red Immediately
Highly Conducive (4)
Pink/white Immediately
Extremely Conducive (5)

26. Advantages
No incubation
Quick results
Disadvantages
Results vary with time after food intake & after brushing

27. 5.ALBAN TEST Simple modified Snyder test Main Features:
softer medium that permits the diffusion of saliva and acids without melting the medium.
simpler sampling procedure , patient expectorates directly into tubes containing the medium
Essentials of Preventive and community Dentistry- Soben Peter

28. following materials are required:
Synder test agar
A small scale to measure 60 grams.
A 2 litter Pyrex glass to melt the medium.
A funnel to dispense the medium into test tubes.
mm test tubes with screw caps

29. Procedure :
60gms of Snyder test agar is placed in 1 litre of water &suspension is brought to a boil over a low flame.
When thoroughly melted the agar is distributed
The tubes are autoclaved for 15 minutes: allowed to cool and stored in a refrigerator.
2 tubes are taken & the patient is asked to expectorate a small amount of saliva directly into the tubes.
incubated at 370C for upto 4 days

30. observe for:
Change of colour from bluish green (pH 5) to definite yellow (pH 4 or below).
The depth in the medium to which the change has occurred.

31. Scale for Scoring:
1. No colour change = ‘3/4’
2. Beginning colour change = ‘+’
(from top to medium down)
3. One half colour change = ‘++’
(from top down)
4. Three fourths colour change = ‘+++’
5. Total colour changes to yellow = ‘++++’

32. Advantages:
Simplicity,
Low cost,
Diagnostic value when negative results are obtained.
Motivational value
Disadvantages:
More armamentarium
Subjective evaluation

33. 6. SALIVARY BUFFER CAPACITY
Action
Measures the no. of mls of acid required to lower the pH from 7 to 6.
Equipment
pH meter
0.05N lactic acid
Paraffin
Sterile glass jars containing small amount of oil.
Cariology , 3rd Ed. - Earnest Newbrun

34. Procedure
10ml of saliva collected under oil 1hr after eating
5ml is taken into a beaker
pH of saliva is adjusted to 7.0
Lactic acid is added until pH of 6.0 is reached.
The no. of ml of lactic acid needed to reduce pH is a measure of buffer capacity.
Evaluation :
Inverse relationship

35. 7. STREPTOCOCCUS MUTANS LEVEL IN SALIVA
measures the number of Streptococcus mutans colony forming units per unit volume of saliva
Incubation is done on Mitis Salivarius Agarwith addition of sucrose (20%) & 0.2U bacitracin /ml which supresses the growth of most non-S.Mutans colonies

36. The samples of organisms is obtained by the use of tongue blades
Procedure
The samples of organisms is obtained by the use of tongue blades
Sample then pressed against Mitis Salivarius
Bacitracin Agar in special Petri dishes
incubated at 370C for 48 hrs in 95%& 5%CO2
gas mixture
Cariology , 3rd Ed. - Earnest Newbrun

37. Interpretation : Levels of Streptococcus Mutans > 10 5/ ml of saliva = unacceptable,

38. Disadvantages
Difficulty of distinguishing between a carrier state and cariogenic infection.
S. Mutans may constitute less than 1% of total flora of plaque.
S. Mutans tends to be located at specific sites only.
Not convenient for chair side

39. 8.Dip slide method Dentocult Larmas ,1975 S.Mutans levels in saliva
Procedure
Saliva is collected and poured over the agar coated slide & allowed to dry
Bacitracin disks are placed in the middle
Co2 tablet is inserted in the tube & then incubated for 48 hrs.

40. Colony density (small blue colonies) compared with model chart
negligible
<105
> 106

41. 9.Plaque / tooth pick method
Action
Simple screening of diluted plaque sample
Procedure
Plaque samples are collected from the gingival thirds of buccal tooth surfaces & placed in Ringer’s solution
Suspension is stretched across MSA plates
Incubation at 370C for 72 hrs
Cariology , 3rd Ed. - Earnest Newbrun

42. 10. S. mutans adherence method
Saliva inoculated in MSB broth for 24 hrs at 37°C
After growth, the supernatant removed
Cells adhering to the glass examined macroscopically
SCORE
NO OF COLONIES -
No growth expressed +
Few deposits from 1-10 ++
Scattered deposits of smaller size
+++
Numerous minute deposits & more than 20 large deposits (indicates > 105 CFU/ml)
wS. mutans adherence method
S. mutans dip-slide methods
S. mutans replicate technique
See for all three -newbrun 42

43. 10.Fosdick Calcium dissolution test
Principle
Measures the mgs of powdered enamel dissolved in 4 hours, when patients saliva mixed with glucose and powdered enamel.
Essentials of Preventive and community Dentistry- Soben Peter

44. Advantages
Correlation reported is good
Disadvantages
Complex equipment
Expensive, trained personnel.

45. 11. DEWAR TEST Test similar to fosdick calcium dissolution test
Except that in this test the pH of the mixture is measured instead of the amount of calcium dissolved by the acid.
Essentials of Preventive and community Dentistry- Soben Peter

46. 12. CARIOSTAT TEST Tsutomu Shimono 1974
This test has been reported to significantly correlate with counts of S.mutans in children
uses a semisynthetic liquid containing sucrose, tryptose, a gram-negative bacteria growth inhibitor, and bromcresol green and bromcresol purple indicators.
The test assesses acid production by cariogenic bacteria and thus indirectly assesses caries activity
The sensitivity and specificity of a colorimetric microbiological caries activity test (Cariostat) in preschool children

47. Interpretation of Cariostat test
Score pH
Color
Caries Activity 7
Blue
Caries inactive 1
5.5
Green
Slight caries 2
4.5
Yellow - Green
Moderate caries 3
4.0
Yellow
Marked caries

48. 13.Oratest Rosenberg et al. in 1989 Principle
The rate of oxygen depletion by micro organisms in expectorated milk samples

49. Under aerobic conditions the bacterial enzyme, aerobic dehydrogenase transfers electrons or protons to oxygen.
Once oxygen gets utilized by the aerobic organisms and an anaerobic environment is attained, methylene blue acts as an electron acceptor and gets reduced to leucomethylene blue
The metabolic activity of the aerobic microorganism is reflected by the reduction of methylene blue to leucomethylene blue.
Oratest: A Simple Chairside Aid for Caries Risk Assessment

50. Advantages
Simple , inexpensive , less time consuming , reproducible and requiring no trained personnel.
Used to monitor mouth rinse regime , denture hygine , gingival inflammation and plaque levels.
Good educational and motivational tool for patient,school and community health programmes.
Vehicle for test is nontoxic (milk)
Anticipate the onset of caries
Results can provide dentist to command patient to reinforce motivation ,plaque control and behaviour

51. Disadvantages
It does not identify a specific group of organism in a specific disease.
It cannot accurately differentiate between the healthy state and between initial and progressive carious lesion
Lack of specificity since positive observation can be obtained in gingivitis and other oral ailments.

52. 14. Salivary glucosyltransferase b
Gtfs play a critical role in the pathogenesis of caries and furthermore, the enzymes are present in whole saliva.
Therefore, hypothesized that the amount of Gtfs collectively or separately could be correlated with caries activity.
chair side and provide results within minutes
Salivary Glucosyltransferase B as a Possible Marker for Caries Activity-

53. 2 ml of saliva was collected
saliva was clarified by centrifugation,
Clarified saliva was mixed in a 1:1 ratio with the coating buffer supplied in the kit and was coated onto 96-well plates
After washing, antibodies to Gtf B, C and D were applied
intensity of the color in the wells, which correlated to the amount of purified Gtf present, was read in an ELISA reader

54. 15. CariScreen Caries Susceptibility Test
is done in one minute at chairside
ATP bioluminescence technology, which is a test for light reaction, will measure on a scale from 0 to 9999.
the levels of acid-producing bacteria by swabbing lingual surfaces of lower anterior teeth and then inserting the sample in the CariScreen meter to be read
0 to 1500 is low risk and 1500 to 9999 is high risk
The ATP generates light once it reacts with luciferin, a light- emitting biological pigment/enzyme present in the CariScreen. The amount of light emission is in direct proportion to the amount of ATP and a well-known fact is that acid-producing bacteria contain 100 times more ATP than non-acid-producing strains

56. 16. Carivis
system for assessment of caries activity relies on the unique properties of the Glowdent marker that detects actively occuring dental demineralisation
The amount of light emitted varies with the amount of minerals present
more minerals equals more light.

57. Advantages of the Carivis System
The Carivis caries assessment system marks a new approach in preventive dentistry. Its innovative design offers:
Non-invasive, one-step method
Caries activity assessment is possible with a single visit to the dentist
Extreme sensitivity and information on the extent of demineralisation
Access to all dental surfaces, including contacting surfaces of teeth and around restorations
Ease of use
Speed; signal collection requires less than 10 seconds

59. conclusion

60. References Cariology , 3rd Ed. - Earnest Newbrun
Principles & practice of pedodontics – Arathi Rao
Dentistry for the child & adolescent – McDonald
Textbook of Pedodontics- Shobha Tandon
Textbook of Pediatric dentistry- S.G.Damle
Essentials of Preventive and community Dentistry- Soben Peter
Chair side simple caries activity test: Ora test- Bhasin S, JISPPD 2006;24:2
A Modified dip slide test for microbiological risk in caries assessment.B Thaweboon,srosori thaweboon etal,Southeast Asian J Trop Med Public health; :2:400-04
Salivary Glucosyltransferase B as a Possible Marker for Caries Activity- A.M. Vacca Smith. Caries Res November; 41(6): 445–450
Using a Caries Activity Test to Predict Caries Risk in Early Childhood. Michiko Nishimura, JADA
Oratest: A Simple Chairside Aid for Caries Risk Assessment -Arora Ruchia, Lahiri. Prathik. Kb, Masih Updes. Int. j of dental clinics 2009:1(1): 26-30
The sensitivity and specificity of a colorimetric microbiological caries activity test (Cariostat) in preschool children. Pediatric Dentistry: July/Aug Volume1 6, 4

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