Just as many people have replaced their manual toothbrush with an electric one, so too could robots usher in a new era of teeth cleaning. Scientists have created a swarm of shapeshifting microrobots that they claim can brush, rinse and floss your teeth all at the same time. In a proof-of-concept study, researchers from the University of Pennsylvania showed that the hands-free system could effectively automate the treatment and removal of tooth-decay-causing bacteria and dental plaque. The system could be particularly valuable for those who lack the manual dexterity to clean their teeth effectively themselves, the experts said. The building blocks of these microrobots are iron oxide nanoparticles which have both catalytic and magnetic activity.