Relationship between caries status, colony forming units (cfu) of Streptococcus mutans and Snyder caries activity test.

It is a well established fact that dental caries is caused by streptococcus mutans. For qualitative and quantitative analysis of streptococcus mutans, saliva samples are often preferred and are processed according to Kohler and Brathall method. In the present study an attempt is made to relate caries status (caries free, average caries, and rampant caries group) with cfu counts of streptococcus mutans and Snyder test. The streptococcus mutans were isolated using MSB agar and cfu were determined of each individual from different caries groups. The saliva of the same individual was drooled into a culture bottle containing Snyder test agar and extent of colour change was observed after 24, 48, and 72 hours incubated at 37 degrees C. The time and extent of colour change determined the conduciveness of diet. It has been observed that caries free individuals have low cfu count and their diet was mild or moderately conducive, while the individuals having average caries had medium cfu count and their diet was moderately-high conducive. In rampant caries, individuals however the cfu count were high and the diet was highly conducive. In caries free, average caries and rampant caries group 40, 60, and 80 per cent samples showed colour change, in Snyder test up to full length in 72 hours respectively. Thus a definite correlation exists between caries status, cfu count of streptococcus mutans and Snyder caries activity test.