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Robert F. Cook, David B. Marshall, Nitin P. Padture, Michelle L. Oyen, Antonia Pajares, Jodie E. Bradby, Ivar E. Reimanis, Rajan Tandon, Trevor F. Page, George M. Pharr, Brian R. Lawn
The utility of indentation testing for characterizing a wide range of mechanical properties of brittle materials is highlighted in light of recent articles
A model for the splitting of teeth from wedge loading of molar cusps from a round indenting object is presented. The model is developed in two parts: first, a
Paul Constantino, James J. Lee, Yvonne B. Gerbig, Adam Hartstone-Rose, Mauricio Talebi, Brian R. Lawn, Peter Lucas
Primate teeth adapt to the physical properties of foods in a variety of ways including changes in occlusal morphology, enamel thickness, and overall size. We
A review on the use of sharp, fixed-profile indenters as materials probes is presented. Indentation is proposed as a simple but powerful methodology for
Paul Constantino, James J. Lee, H Chai, Bernhard Zipfel, Charles Ziscovici, Brian R. Lawn, Peter Lucas
Fossil hominin tooth enamel often exhibits antemortem edge chipping (Robinson 1954; Tobias 1967; Wallace 1973). Here we apply a simple fracture nist-equation to
We present definitive evidence for crack growth from internal defects called 'tufts' in human enamel. Side walls of slices sawn from extracted human teeth are
One failure mode of all-ceramic crown restorations is radial cracking at the cementation surface, from occlusally-induced flexure of the stiffer crown layer on
This paper addresses the durability of natural teeth from a materials perspective. Teeth are depicted as 'smart' biocomposites, highly resistant to cumulative
Sang-Won Myoung, James J. Lee, Paul Constantino, Peter Lucas, Brian R. Lawn
Teeth are remarkable biological structures, brittle but resilient. Here we examine the inter-relation between enamel morphology and crack resistance by
Brian R. Lawn, David Strait, Gerhard Weber, Simon Neubauer, Janine Chalk, Brian Richmond, Peter Lucas, Mark Spencer, Caitlin Schrein, Paul Dechow, Callum Ross, Ian Grosse, Barth Wright, Paul Constantino, Bernard Wood, Qian Wang, Dennis Slice, Craig Byron, Amanda Smith
The African Plio-Pleistocene hominins known as australopiths evolved a distinctive craniofacial morphology that traditionally has been interpreted as a dietary
Brian R. Lawn, James J. Lee, Paul Constantino, Peter Lucas
Dentition is a vital element of human and animal function, yet there is little fundamental knowledge about how tooth enamel endures under stringent oral
James Lee, Isabel K. Lloyd, Herzl Chai, J G. Jung, Brian R. Lawn
A layer structure consisting of two glass plates bonded with polymer-based adhesives and loaded at the upper surface with a line indenter is used to evaluate
Sanjit Bhowmick, Juan J. Melendez-Martinez, Brian R. Lawn
It has long been held that bulk silicon is immune from fatigue. We present contrary evidence demonstrating severe fatigue in macroscale cracks produced in
James J. Lee, H Chai, Isabel K. Lloyd, Brian R. Lawn
Crack propagation across interlayers separating adjoining brittle plates in flexure is studied using a model glass/epoxy/glass system. A transverse starter
An earlier analysis of chipping fracture in brittle solids is here extended to include the case of blocks with inclined side faces and non-normal contact
Brian R. Lawn, Sanjit Bhowmick, M T. Bush, T Qasim, E D. Rekow, Yang Zhang
A research program on failure modes induced by spherical indenters in brittle layer structures bonded to polymeric substrates, in simulation of occlusal
The role of a tangential load component in cyclic contact-induced failure of a brittle coating layer is investigated. Tests are conducted on model bilayer