Researchers (IMAGE) University of Copenhagen - Niels Bohr Institute Caption Heloisa Bordallo, materials researcher at the Niels Bohr Institute at the University of Copenhagen and Ana Benetti, dentist and researcher at the Faculty of Health and Medical Sciences at the University of Copenhagen, collaborate in the development of a strong material for tooth fillings made out of glass ionomer cement. Credit (Credit: Ola Jakup Joensen, NBI) Usage Restrictions (Credit: Ola Jakup Joensen, NBI) 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.