Robot Cleaning the inside of a Tooth (IMAGE) University of Pennsylvania Caption The Penn team's micro-robots were effective at cleaning hard-to-reach surfaces. This time-lapse image shows one of their molded, helicoid-shaped robots traveling inside a tooth canal. Credit Alaa Babeer, Elizabeth E. Hunter, and Hyun Koo. Usage Restrictions In context of reporting License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.