Spinosaurus teeth (IMAGE) Utrecht University Caption The most common tooth type, of the famous Spinosaurus, with characteristic sail on its back. Credit Image from article discussed. Usage Restrictions Use with acknowledgement of original source permitted. License Original 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.