27 Apr Saliva: Protector of Teeth
Saliva is more important than you think, as recent research has shown that saliva helps protect the teeth from cavities. Saliva is comprised with mostly water, but 0.5% of saliva is mucus; mucus contains salivary mucins, which are large glycoproteins that are now known to actively protect the teeth from damage by Streptococcus mutans, a cavity-causing bacterium.
It was originally thought that salivary mucins role has been to just keep the mucus in saliva elastic and slippery; contributing to mucus’ gel-like properties. However, current research findings in the journal Applied and Environmental Microbiology have shown that the salivary mucins play an active role in the defense against pathogens, as well as help keep the human microbiome strong and healthy. The findings in the journal Applied and Environmental Microbiology, were reported by first author Erica Shapiro Frenkel from Harvard University, as well as principal investigator Katharina Ribbeck, a Massachusetts Institute of Technology professor. These researchers discovered that the levels of S. mutans are not altered, or destroyed, by the salivary mucins; instead, the salivary mucins actually help keep the S. mutans suspended in your saliva. This helps prevent S. mutans from being able to form a biofilm on the teeth, as well as help keep the oral microbiome, a collection of good bacteria, better preserved by not killing off any of the naturally present species of bacteria.
Tooth decay and cavities are caused when the bacterium, S. mutans, attaches to the tooth and forms a biofilm from the sticky polymers that it secretes. A densely packed community of microbes grows protected under the biofilm, and as this bacterium grows, organic acid by-products created attack the tooth enamel. This biofilm growing on the surface of teeth is what leads to cavities, as well as deterioration of the teeth. However, now knowing that salivary mucins help prevent the formation of the biofilm, is a huge step towards the prevention of tooth decay and cavities!