Teeth (IMAGE) R&D at British American Tobacco Caption From the top, teeth exposed to (1) smoke extract (2) e-cig extract (3) glo extract (4) solvent with no extract. Credit British American Tobacco Usage Restrictions None 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.