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Module 1: Tooth Decay

1.2 What is Streptococcus Mutans?

The bacterium S. mutans is the main contributor to tooth decay. S. mutans can grow under conditions that would kill other bacteria.

S. mutans is found mostly on tooth surfaces. One tooth may have a large number of these bacteria, while the tooth next to it may have only a small number. The bacteria are most concentrated in the crevices, pits, and fissures that are a normal part of the teeth and surrounding structures.

teeth with decay

Teeth with decay


The quantity of S. mutans in the mouth during infancy may be an excellent predictor of tooth decay in early childhood