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Fracture in teeth-a diagnostic for inferring bite force and tooth function

2011; Wiley; Volume: 86; Issue: 4 Linguagem: Inglês

10.1111/j.1469-185x.2011.00181.x

1469-185X

James J.-W. Lee, Paul J. Constantino, Peter W. Lucas, Brian R. Lawn,

Turtle Biology and Conservation

Biological ReviewsVolume 86, Issue 4 p. 959-974 Fracture in teeth—a diagnostic for inferring bite force and tooth function James J.-W. Lee, Corresponding Author James J.-W. Lee Ceramics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA (E-mail: [email protected]).Search for more papers by this authorPaul J. Constantino, Paul J. Constantino Department of Anthropology, Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052, USA Department of Biology, Marshall University, Huntington, WV 25755, USASearch for more papers by this authorPeter W. Lucas, Peter W. Lucas Department of Anthropology, Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052, USASearch for more papers by this authorBrian R. Lawn, Brian R. Lawn Ceramics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA Department of Anthropology, Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052, USASearch for more papers by this author James J.-W. Lee, Corresponding Author James J.-W. Lee Ceramics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA (E-mail: [email protected]).Search for more papers by this authorPaul J. Constantino, Paul J. Constantino Department of Anthropology, Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052, USA Department of Biology, Marshall University, Huntington, WV 25755, USASearch for more papers by this authorPeter W. Lucas, Peter W. Lucas Department of Anthropology, Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052, USASearch for more papers by this authorBrian R. Lawn, Brian R. Lawn Ceramics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA Department of Anthropology, Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052, USASearch for more papers by this author First published: 20 April 2011 https://doi.org/10.1111/j.1469-185X.2011.00181.xCitations: 62Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Abstract Teeth are brittle and highly susceptible to cracking. We propose that observations of such cracking can be used as a diagnostic tool for predicting bite force and inferring tooth function in living and fossil mammals. Laboratory tests on model tooth structures and extracted human teeth in simulated biting identify the principal fracture modes in enamel. Examination of museum specimens reveals the presence of similar fractures in a wide range of vertebrates, suggesting that cracks extended during ingestion or mastication. The use of 'fracture mechanics' from materials engineering provides elegant relations for quantifying critical bite forces in terms of characteristic tooth size and enamel thickness. The role of enamel microstructure in determining how cracks initiate and propagate within the enamel (and beyond) is discussed. The picture emerges of teeth as damage-tolerant structures, full of internal weaknesses and defects and yet able to contain the expansion of seemingly precarious cracks and fissures within the enamel shell. 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