‘Superorganisms’ leaping across teeth causing tooth caries

06 October 2022

A team of researchers have discovered bacteria and fungi which lead to dental caries can team up to create ‘superorganisms’.

A team of researchers have discovered bacteria and fungi which lead to dental caries can team up to create ‘superorganisms’.

Lead by scientists at the University of Pennsylvania School of Dental Medicine discovered the organisms while studying the saliva of “toddlers with severe tooth decay”. These ‘superorganisms’ had a higher resistance to antimicrobials and proved harder to remove from teeth than bacteria or fungi alone.

Under a microscope, the team discovered the organisms could sprout “limbs” which allow them to “leap” across teeth.

Hyun (Michel) Koo, a professor at Penn Dental Medicine and a co-corresponding author on the paper said to PennToday, “Looking under the microscope, we noticed the bacteria and fungi forming these assemblages and developing motions we never thought they would possess: a ‘walking-like’ and ‘leaping-like’ mobility. They have a lot of what we call ‘emergent functions’ that bring new benefits to this assemblage that they could not achieve on their own. It’s almost like a new organism—a superorganism—with new functions.”

The organisms were also found to be incredibly fast-moving, with measured velocities of 40 microns per hour (similar to the speed of fibroblasts cells used in wound healing). Just hours after their first growth they were able to “leap” more than 100 microns across the surface. “That is more than 200 times their own body length,” says Zhi Ren, a postdoctoral fellow in Hyun Koo’s group. Scaled up, this would be “better than most vertebrates, relative to body size. For example, tree frogs and grasshoppers can leap forward about 50 times and 20 times their own body length, respectively.”

Due to how swiftly the organism moves they are able to quickly colonise and spread. Laboratory model testing on human teeth showed increased and “extensive” rates of tooth decay due to the rapidly spreading biofilm.

Hyun Koo suggested the future of the research is in attempting to “block this binding or disrupt the assemblage before it arrives on the tooth and causes damage, that could be a preventive strategy.”

Read the full study here: https://www.pnas.org/doi/full/10.1073/pnas.2209699119