The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.for more details please visit  www.indiandentalacademy.com

1. DENTAL CARIES
• INDIAN DENTAL ACADEMY
Leader in continuing Dental Education
www.indiandentalacademy.com

2. LEARNING OBJECTIVES
 At the end of the lecture student should be
able to
– Enlist commonly employed caries activity tests
– Describe positive and negative points for all the
diagnostic tests
www.indiandentalacademy.com

3. CARIES ACTIVITY TESTSCARIES ACTIVITY TESTS
• Caries activity test have been used in dental research for
many years. Some test have been routinely used in dental
office. There is no ideal test in existence at the present
time, although caries activity tests are a valuable adjucent
for patient motivation
• Uses of caries susceptibility tests
www.indiandentalacademy.com

4. For the clinician
1) To determine the need for caries control
2) As an indicator of patient co –operation
3) To act as an aid in timing of recall appointments .
4) As a guide to insertion of expensive restoration.
5) To aid in the determination of prognosis
6) As a precautionary signal to the orthodontist in
placing bands.
www.indiandentalacademy.com

5. CARIES ACTIVITY TESTS
Lactobacillus colony count
Sydner Test
Reductase test
Buffer Capacity test
Forsdick Calcium dissolution test
Dewar test
Mutant group of streptococci screening test
www.indiandentalacademy.com

6. Saliva /tongue blade method
S. mutans adherence method
S mutans dip slide method
S.mutans replicate technique
Cariostat.
www.indiandentalacademy.com

7. LACTO BACILLUS COLONY
COUNT
(Hardley 1933)
ACTION :- To estimate the number of acidogenic and
acid uric bacteria in the patients salvia by counting
the number of colonies appearing on tomato peptone
agar plates (PH.5.0) after inoculation with a sample
of salvia.
EQUIPMENT : Salvia collecting bottles, Paraffin,
two 9-ml tubes of saliva, two agar plates, two bent
glass rods, Quebec counter and pipettes.www.indiandentalacademy.com

8. PROCEDURE: Saliva is collected in a bottle after
having the subject chew, paraffin before breakfast.
A 1:10 dilution is prepared by pipetting 1ml of the
saliva sample into a 9ml tube of sterile saliva
solution. This is shaken and a 1:100 dilution is made
by pipetting 1ml of the 1:10 dilution into another 9ml
tube of sterile salt solution.
www.indiandentalacademy.com

9. SNYDER TEST:
Action : Measures the rapidity of acid formation
when a sample of stimulated saliva is inoculated into
glucose agar adjusted to Ph 4.7 and with bromocresol
green color indicator.
Equipment : Saliva collecting bottles , Paraffin a tube
of Sydner glucose agar containing bromocresol green
and adjusted to PH .4.7 to 5 pipettes and incubating
facilities.
www.indiandentalacademy.com

10. Procedure: Saliva is collected before break fast by
having the subject chew paraffin. A tube of Sydener’s
glucose agar is melted and the cooled to 50° C. The
saliva specimen is shaken vigorously for 3 minutes.
The 0.2 ml of saliva is pipetted into the tube of agar
and immediately mixed by rotating the tube .
www.indiandentalacademy.com

11. . The agar is allowed to solidify in the tube and is
incubated at 37°C. The color change of the
indicator is observed b after 24, 48 and 72 hours
of inculcation by comparison with a uninoculated
tube against a white back ground.
Results 24hours 48 hours 72hours
Color yellow yellow yellow
Caries activity Marked definite limited
Color Green green green
Caries activity Continue test continue test inactive
www.indiandentalacademy.com

12. REDUCTASE TEST :
Action: Measures the rate at which an indicator
molecule, diazoresorcinol changes from blue to red
to colorless or leukoform on reduction by the mixed
salivary flora. The test “measures the activity of a
single Enzyme” , reductase.
Equipment : The Reductase test comes in a kit
(Treatex, C.W. Erwin and Co) that includes calibrated
saliva collection tubes with the reagent on the inside
of the tubes, cap, plus flavored Paraffin.
www.indiandentalacademy.com

13. Procedure : Saliva is collected by chewing a special
flavored Paraffin and expectorating directly into the
collection tube. When the saliva reaches the
calibrated mark (5ml). The reagent cap is replaced.
The sample is mixed with a fixed amount of
diazoresorcinol the reagent upon which the reductive
enzyme is to react. The change in color after 30 sec
and after 15 minutes is taken as a measure of caries
actively.
www.indiandentalacademy.com

14. Results Time Score Caries Activity
Color 15min 1 Non conducive
Blue 15min 2 Slightly conducive
Orchid 15min 3 Moderately
conducive
Red Immediately 4 Highly conducive
Pink or White Immediately 5 Extremely
conducive www.indiandentalacademy.com

15. SUMMARY
– various commonly employed caries activity
tests
– positive and negative points for all the
diagnostic tests
www.indiandentalacademy.com

16. BIBLIOGRAPHY
Text book of oral pathology Shafer's, 5 & 6th
edition
Color Atlas of Oral Diseases Cawson, R. 2nd
edition
Oral and Maxillofacial Pathology Neville, Brad
W. 2nd
Lucas’s Pathology Of Tumor’s of the Oral Tissues
Cawson, R. A., Bennie, W. H 5th
editionwww.indiandentalacademy.com

17. THANK YOU
www.indiandentalacademy.com