BRUSHING your teeth does more than just clean them. It also wreaks havoc on the social lives of the bacteria that are left – and this familial disruption probably makes them less able to rot your teeth.
Oral bacteria, like many other microbes, live in a protective chemical matrix called a biofilm. The biofilm restricts their movements, so bacteria tend to grow in family groups. This allows them to thrive by evolving cooperative relationships with neighbouring kin, says biologist Kevin Foster of the Institute for Advanced Study in Berlin, Germany.
Brushing disrupts these cosy relationships, leaving the bacteria surrounded by strangers.…
