title: Sea otter dental enamel is highly resistant to chipping due to its microstructure.
abstract: Dental enamel is prone to damage by chipping with large hard objects at forces that depend on chip size and enamel toughness. Experiments on modern human teeth have suggested that some ante-mortem chips on fossil hominin enamel were produced by bite forces near physiological maxima. Here, we show that equivalent chips in sea otter enamel require even higher forces than human enamel. Increased fracture resistance correlates with more intense enamel prism decussation, often seen also in some fossil hominins. It is possible therefore that enamel chips in such hominins may have formed at even greater forces than currently envisaged.
authors.affiliation: Department of Anthropology, Center for the Advanced Study of Human Paleobiology, George Washington University, Washington, DC 20052, USA.
authors.forename: Charles
authors.initials: C
authors.lastname: Ziscovici
authors.affiliation: Department of Bioclinical Sciences, Faculty of Dentistry, Kuwait University, PO BOX 24923, Safat 13110, Kuwait pwlucas@gmail.com.
authors.forename: Peter W
authors.initials: PW
authors.lastname: Lucas
authors.affiliation: Department of Biology, Saint Michael's College, Colchester, VT 05439, USA.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Constantino
authors.affiliation: Department of Biomaterials and Biomimetics, New York University College of Dentistry, 345 East 24th Street, New York, NY 10010, USA Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, 345 East 24th Street, New York, NY 10010, USA.
authors.forename: Timothy G
authors.initials: TG
authors.lastname: Bromage
authors.affiliation: Department of Bioclinical Sciences, Faculty of Dentistry, Kuwait University, PO BOX 24923, Safat 13110, Kuwait Max Planck Weizmann Center for Integrative Archaeology and Anthropology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig 04103, Germany.
authors.forename: Adam
authors.initials: A
authors.lastname: van Casteren
mesh_terms: D000818:Animals; D001732:Bite Force; D003743:Dental Enamel / Q000293:injuries* / Q000648:ultrastructure*; D015186:Hominidae; D010041:Otters; D014070:Tooth / Q000033:anatomy & histology; D014082:Tooth Fractures
keywords: chipping; dental enamel; toughness