According to Kelly Swanson and his colleagues from the University of Illinois, the bacteria responsible for causing dental caries are present in infants’ mouths even before the eruption of their baby teeth.
Cavities, or dental caries, are actually bacterial infections of the teeth. By the time children reach preschool age, more than a quarter of them will already have cavities. For this reason, the researchers decided to see whether they could detect caries-causing bacteria in infants even before the children have any teeth. The answer was that they could.
Swanson’s team sequenced the DNA of all the salivary bacteria found in five toothless babies and their mothers. About 400 different bacterial genera were present in the samples. Although infants had only about half as many types of bacteria as the adults, they still had more than enough of the caries-causing pathogens to infect their teeth as they erupted.
Obviously, this was an extremely small study. More work must be done to see whether differences in feeding practices can affect the results. However, the results do suggest that in order to prevent cavities, oral care should begin even before children have any teeth.