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Module 1: Tooth Decay

1.3 Can a Parent “Infect” an Infant or Child with Streptococcus Mutans?

Adults may have a high concentration of S. mutans in their mouths. Bacteria can be transmitted from a parent or another caregiver to an infant or child via saliva, for example, by allowing infants or children to put their fingers in the parent’s mouth and then into their own mouths, testing the temperature of a bottle with the mouth, sharing forks and spoons, and “cleaning” a pacifier or a bottle nipple that has fallen by sucking on it before giving it back to the infant or child.

Even if an infant or child is already infected with S. mutans, transmission can increase the concentration of bacteria in the infant’s or child’s mouth, increasing the likelihood of tooth decay or resulting in more severe decay. Therefore, it is important that parents and other caregivers practice good oral hygiene and avoid behaviors that could transmit S. mutans to an infant or child.

Case Study #001

A mother tells you that between taking care of her three children (ages 5, 3, and 6 months) and working full time, she doesn't have time to brush her teeth, let alone floss. What should you do?

text version

baby putting hand in mother's mouth while feeding


Having tooth decay in early childhood dramatically increases a child’s risk of having tooth decay in the future.