Saliva Protects Teeth Against Cavities Better Than We Thought

Our mouth is home to millions of species of bacteria and the surface of our tongue alone is home to 50% of those bacteria. But our mouth also has the ability to naturally fight off cavity-causing bacteria. Healthy saliva is a critical part of our mouth’s defence mechanism.

Saliva neutralises acids in the mouth and contains compounds that naturally strengthen our teeth. One of these compounds is the salivary mucins, which a recent study shows play an active role in preventing cavity-causing bacteria from forming a biofilm—commonly called Plaque. The mucins do this by surrounding the bacteria before they have a chance to settle on the teeth: the bacteria are instead kept in suspension in the saliva and swallowed.

The bacterial species that is considered to be the one most likely to cause decay is Streptococcus Mutans, or S. mutans for short.

The study reported that:

“(Salivary mucins) limit biofilm formation by keeping S. mutans suspended in the liquid medium. This is particularly significant for S. mutans because it only causes cavities when it is attached, or in a biofilm on the tooth’s surface.”

The author of the study, Erica Shapiro Frenkel of Harvard University, suggests that “boosting the body’s natural defences might be a better way to prevent tooth decay than relying on external agents like sealants and fluoride treatments”.