Jing Du
Department of Mechanical and Nuclear Engineering, PSU

Wednesday, October 12, 2016 3:35pm - 4:25pm
103 Leonhard Building

Abstract:
Caries, which lead to partial or total loss of teeth, influence almost 100% adults and 60-90% of school children. To restore the function and appearance of teeth, dental crowns have been adopted as a common treatment. However, the strength and fatigue life of the crowns are not satisfactory due to many reasons. Natural teeth have superior performance both in strength and durability to the artificial dental structures. In this study, inspired by the crack resistance of the functionally graded structure of natural teeth, a bio-inspired design of functionally graded dental material was proposed to replace the conventional dental adhesive material. Numerical models were used to optimize the design. Guided by the models, nanocomposite materials were used to fabricate these graded structures. Under Hertzian contact loading, they had ~2030% higher critical loads than conventional dental multilayers at various clinically relevant loading rates. The critical loads were also well predicted by fracture mechanics models that integrated the nanoindentation measurements and creep test of the fabricated graded materials. The failure modes of the structure were also investigated to make connections to the clinical failure modes of dental crowns.

Bio:
Dr. Jing Du is an assistant professor of mechanical engineering at Penn State University. She received her B.S. and M.S. degrees in Mechanical Engineering and Materials Science and Engineering, respectively, from Tsinghua University and a Ph.D. degree in Mechanical & Aerospace Engineering from Princeton University. Before joining Penn State, she was a postdoctoral scholar in the School of Dentistry at the University of California, San Francisco (UCSF). Her research focuses on solid mechanics and materials science. Her current areas of research interests include mechanics of biological materials and biomaterials, biomedical devices and bio-inspired design.