PHILADELPHIA, May 24, 2021 / PRNewswire / – A high-carb diet and poor oral hygiene can leave children with early childhood tooth decay (ECC), a severe form of tooth decay that can have profound effects on oral and overall health.
A few years ago, researchers at Penn Dental Medicine found that the dental plaque that leads to ECC consists of both a type of bacteria, Streptococcus mutans, and a fungus, Candida albicans. The two form a sticky biofilm that is difficult to remove from the tooth surface.
Now, a new study by the group offers a strategy for disrupting this biofilm by targeting the interactions between yeast and bacteria.
“This gives us another tool for disrupting this virulent biofilm,” says Geelsu Hwang, assistant professor at Penn Dental Medicine and lead author of the study published in mBio.
The work builds on earlier findings from Hwang, who showed molecules called mannans on the Candida cell wall that are tightly bound to an enzyme secreted by S. mutans, glycosyltransferases (Gftb). Not only does Gftb facilitate cross-kingdom bonding, it also contributes to the stubbornness of dental biofilms by making glue-like polymers (glucans) in the presence of sugars.
While some cases of ECC are treated with antimicrobial agents that kill the microbes directly, the biofilm is not always broken down and can affect “good” microbes as well as the soft tissues of the oral cavity.
Wanting to try a different approach that involved the interaction between yeast and bacteria, Hwang and colleagues decided to target the mannans in the Candida cell surface.
They applied three different mannan-degrading enzymes to a biofilm growing on a tooth-like surface in a human saliva medium and allowed it to stand for five minutes. After treatment, the total volume and thickness of the biofilm was reduced along with the bacteria-yeast interactions.
“The biofilm structure was more fragile after the enzyme treatment,” says Hwang. “We could see that the biofilms could be removed more easily.”
The researchers kept the application time relatively short at five minutes, although they hope to see activity in the two minutes recommended for brushing teeth. According to Hwang, an alcohol-based mouthwash with these enzymes could potentially be used as a preventive measure against ECC.
The researchers hope to pursue this possibility with additional follow-up, including testing these enzymes in an animal model. With further success, they want to add another tool to combat the public health threat posed by the ECC.
SOURCE Penn Dentistry