The bond between mother and child is a precious thing — but did you know it can go beyond cuddles and passing on your eye color to your little one? Many mothers are unaware that they can unknowingly impact the oral health of their children.
As surprising as it may seem, cavities are in fact contagious in the sense that dental caries – or bacteria that colonize the mouth and cause cavities – can be passed from a mother’s saliva to their baby’s mouth.
Mutans streptococci (MS) are the most common cavity-causing bacteria, but several other species are also associated with dental caries. The bacteria consume food particles, particularly sugar and starch, and produce acid, which causes demineralization of the tooth.
The most interesting part? We aren’t born with these bacteria in our mouths – we have to be infected, and more often than not, it occurs through Maternal Child Transmission. Evidence for this transmission comes from several studies revealing that the genetic makeup of the mutans streptococci in mothers and their babies are similar or identical.
This passage of decay-causing bacteria from mother to baby requires the presence of a tooth and, thus, typically begins around four to six months. Studies conducted in the 1980’s identified mothers as the main source of bacterial colonization in an infant’s mouth, though any primary caregiver can also pass decay-causing bacteria to a child.
Examples of how this transmission can occur are:
- Pre-chewing a baby’s food, or sharing a spoon during meals.
- Cleaning a baby’s pacifier in the mother’s mouth before giving it to the baby
- Infant sucking on adult finger
Other identified risk factors for early childhood MS infection have included nighttime nursing, early introduction of solid foods and exposure to sugar. On the other hand, infants whose gums were cleaned daily had a lower incidence of infection.
Can Maternal Child Transmission be prevented?
Because of the link between maternal infection with Mutans streptococci and the risk for early childhood caries, several studies have looked at interventions to reduce the amount of this cavity-causing bacteria in new and expecting mothers through intervention such as oral hygiene and dietary counseling, teeth cleaning, fluoride treatment, and excavation of large cavities. Xylitol gum has also been tested as an alternative approach to reducing maternal Mutans streptococci infection and thus, transmission to baby. Xylitol inhibits the growth of the bacteria and decreases their ability to stick to teeth. To date, three studies have found that when mom chewed xylitol gum 2-3 times per day, beginning before baby’s teeth erupt or even during pregnancy, bacteria colonization of baby’s mouth was delayed and reduced and caries were reduced at age 5. This approach is low-cost and an easy addition to good dental hygiene and care.