2. INTRODUCTION:
CARIES ACTIVITY TESTS HAVE BEEN USED IN
DENTAL RESEARCH FOR MANY YEARS AND
SOME HAS BEEN USED TO DETECT CARIES IN
DENTAL OFFICE.
CARIES ACTIVITY REFERS TO THE INCREMENT
OF ACTIVE LESIONS OVER A STATED PERIOD
OF TIME.
IT REFERS TO THE DEGREE TO WHICH THE
LOCAL ENVIRONMENT CHALLENGE I.E
DIETARY EFFECT ON MICROBIAL GROWTH
AND METABOLISM FAVOURS THE PROBABLITY
OF OCCURRENCE OF CARIOUS
ENVIRONMENT.
3. USE OF CARIES SUSCEPTIBILITY TEST:
IDENTIFY HIGH RISK GROUPS AND
INDIVIDUALS.
DETERMINE THE NEED FOR PERSONALISED
PREVENTIVE MEASURES AND MOTIVATE THE
INDIVIDUAL.
MONITOR THE EFFECTIVENESS OF ORAL
HEALTH PROGRAMS FOR FUTURE
EVALUATION.
ENSURE LOW LEVEL OF CARIES ACTIVITY
BEFORE STARTING ANY EXTENSIVE
PROCEDURE.
SERVES AS SUCCESS OF THERAPY BY
MONITORING THE NO. OF S. MUTANS.
4. IDEAL REQUIRMENTS OF CARIES
ACTIVITY TEST:
SHOULD HAVE A SOUND THEORITICAL
PROCESS.
SHOULD SHOW MAXIMUM CORRELATION WITH
CLINICAL STATUS.
SHOULD BE SIMPLE.
SHOULD BE INEXPENSIVE.
SHOULD TAKE LESS TIME.
5. 1. LACTOBACILLUS COLONY COUNT
TEST:
PRINCIPLE:
- THE TEST ESTIMATES THE NO. OF
ACIDOGENIC AND ACIDURIC BACTARIAIN
PATIENTS SALIVA BY COUNTING THE NO. OF
COLONIES APPEARING ON TOMATO PEPTONE
AGAR PLATE (PH 5.0) AFTER INOCULATION
WITH A SAMPLE OF SALIVA.
6. PROCEDURE:
SMALL PIECE OF PARAFFIN BEFORE BREAKFAST IN
MORNING AND SALIVAL IS COLLECTED IN STERILE
CONTAINER AND SHAKEN.
SAMPLE IS DILUTED IN 1: 10 BY ADDING 1 ML OF SALIVA
TO 9 ML OF SALINE.
THEN IT IS DILUTED INTO 1: 100 BY ADDING 1: 10 IN TO 9
ML OF SALINE.
0.4 ML OF EACH IS SPREAD ON THE AGAR PLATEAND
INCUBATED FOR 3-4 DAYS AT 37 DEGREE.
THEN COLONY IS COUNTED USING COLONY COUNTER.(
QUEBAC COUNTE).
NO. OF LACTOBACILLI 0-1000 – LITTLE, 1000-5000 –
SLIGHT ACTIVITY, 5000-10,000 – MODERATE ACTIVITY, >
10,000 – MARKED ACTIVITY.
7. COLORIMETRIC SNYDER TEST:
PRINCIPLE:
- IT MEASURES THE ABILITY OF SALIVARY
MICROORGANISMS TO FORM ORGANIC ACIDS
FROM A CARBOHYDRATE MEDIUM.THE
MEDIUM CONTAINS AN INDICATOR DYE
BROMOCRESOL GREEN THIS DYE CHANGES
FROM GREEN TO YELLOW IN THE RANGE OF
PH FRP, 5.4 TO 3.8. IT ALSO MEASURES
ACIDURIC AND ACIDOPHILLIC BACTARIA.
8. PROCEDURE:
SALIVA IS COLLECTED BY CHEWING PARAFFIN
BEFORE BREAKFAST IN THE MORNING.
A TUBE CONTAINING SNYDER GLUCOSE AGAR IS
MELTED AND COOLED TO 50 DEGREE. THEN 0.2 ML
OF SALIVA IS ADDED TO THE TUBE AND MIXED ,
THE AGAR IS ALLOWED TO SOLIDIFY AND THEN
INCUBATED AT 37 DEGREE CELSIUS.
AMOUNT OF ACID PRODUCED IS MEASURED BY
COLOUR CHANGES IN PH INDICATOR AND
COMPARED TO UNINOCULATED CONTROL TUBE
AGAINST A WHITE BACKGROUND AFTER 24, 48, 72
HOURS OF INCUBATION.
24 HOURS- YELLOW MARKED - ACTIVITY
9. SWAB TEST:
IN THIS COLLECTION OF SALIVA IS NOT
NEEDED.
PRINCIPLE:
- SWAB IS TAKEN FROM BUCCAL SURFACE OF
TEETH USING COTTON APPLICATOR.
- WHEN PH IS <4.1 – MARKED ACTIVITY, 4.2 – 5.4
– ACTIVE, 4.5 – 5.6 – SLIGHT ACTIVE.
10. S.MUTANS LEVEL
PRINCIPLE:
- MEASUREMENT OF S MUTANS IS DONE FROM
SALIVA . INCUBATION IS DONE IN MITIS
SALIVARIUS AGAR SELECTIVE STREP. MEDIUM
WITH HIGH CONC. OF SUCROSE AND 0.2 U
BACTRACIN / ML SUPRESS THE S . MUTANS.
11. PROCEDURE:
SAMPLE IS OBTAINED USING TONGUE BLADE.
THEY ARE THEN PRESSED AGAINST MSB
AGAR IN PETRI DISHES.
AGAR PLATES AR THEN INCUBATED AT 37
DEGREE FOR 48 HRS IN 95% AT 5% CO2 GAS
MIXTURE.
12. SALIVARY BUFFER CAPACITY TEST
PRINCIPLE:
- BUFFER CAPACITY CAN BE QUANTITATED
USING EITHER PH METEER OR COLOR
INDICATOR. IT MEASURE THE AMOUNT OF
ACID REQUIRED TO LOWER THE PH OF SALIVA
THROUGH A ARBITRARY PH EG 6 – 7
- COLOR INDICATORS ARE USED.
13. PROCEDURE:
TEN ML OF SALIVA IS COLLECTE USING
PARRAFIN WAX. ATLEAST 1 HOUR AFTER
EATING.
5 ML IS COLLECTED IN A BEAKER , AFTER
CRRECTING THE PH METER TO ROOM TEMP.
THE PH OF SALIVA IS CORRECTED TO 7.0
USING LACTIC ACID OR BASE.
IT IS ADDED UNTIL THE PH REACHES 6.0.
THE AMOUNT OF LACTIC ACID NEEDED TO
RAISE THE PH TO 7 OR 6 IS THE BUFFER
CAPACITY.
THE AMOUNT CAN BE CONVERTED TO MILLI
EQ. PER LITRE.
14. SALIVARY REDUCTASE TEST:
PRINCIPLE: THIS TEST MEASURES THE ACTIVITY
OF SALIVARY REDUCTASE ENZYME.
PROCEDURE:
- SALIVA IS COLLECTED.
- MIXED WITH AZORESORCINOL DYE.
- NOW THE COLOR CODUCIVENESS IS CHECKED.
- RESULTS: BLUE COLOR IN 15 MIN – NO CARIES
ACTIVITY, ORCHID COLOR – SLIGHTLY
CONDUCIVE, RED – MODERATELY CONDUCIVE,
PINK- IMMEDIATE CHANGE THEN THE TEST IS
EXTREMELY CONDUCIVE.
15. ORA TEST:
IS IS BASED ON THE OXYGEN DEPLETION BY
MICROBES IN EXPECTORATED MILK
SOLUTION. IN NORMAL CONDITIONS THE
BACTARIA ENZYME AEROBIC
DEHYDROGENASE TRANSFERS ELECTRONS
OR PROTONS TO O2. ONCE THE OXYGEN
GETS UTILIZED BY THE AEROBIC ORGANISMS
METHYLENE BLUE ACTS AS AN ELECTRON
ACCEPTOR AND GETS TRANSFORMED TO
LEUCOMETHYLNE BLUE.
16. PROCEDURE:
MOUTH IS RINSED VIGOUROUSLY WITH 10 ML OF
STERILE MILK FOR 30 SEC AND THEN
EXPECTORATE IS COLLECTED.
3 ML OF THIS TRANSFFERED TO SCREW CAP
TUBE WITH HELP OF DISPOSABLEE SYRINGE.
TO THIS 0.12 ML OF 0.1 % OF METHYLENE BLUE IS
ADDED AND MIXED IN A WELL ILLUMINATED AREA.
THE TUBES ARE OBSERVED FOR COLOR CHANGE
EVERY MINUTES.
THE TIME TAKEN FOR INITIATION OF COLOR
CHANGE WITHIN 6 MM RING IS RECORDED.
HIGHER THE INFECTION LESSER THE TIME TAKEN
FOIR COLOR CHANGE.
