While studying the source of a tooth’s strength, researchers from Tel Aviv University’s School of Mechanical Engineering, the National Institute of Standards and Technology, and George Washington University discovered principles that could inspire future air- and spacecraft. The researchers subjected extracted teeth to varying degrees of mechanical pressure and studied what occurred on the surface and deep inside each tooth. Their findings, published in the May 5, 2009 , issue of the Proceedings of the National Academy of Science, found that tooth enamel owes its strength to a network of micro-cracks that diffuse stress, and that teeth can heal those micro-cracks over time.

While airplane bodies currently use composite materials made from layers of glass or carbon fibers and use a brittle matrix to hold them together, the structure of teeth differs in that the fibers aren’t arranged in grids but are wavy in their structure. In addition, the fibers and matrices in teeth are arranged in several layers, unlike the single thickness layers found in aircraft. The structure of teeth provides such resilience because it presents no clear paths for the release of pressure, resulting in the micro-cracks that prevent splits and fractures. Aerospace researchers say that replicating this capacity could not only help dentists invent stronger crowns and smarter materials – it could help aerospace engineers create a new generation of stronger, lighter air- and spacecraft. Imagine the ability of an airplane or spacecraft to be able to self heal in the future. Who knew that teeth of all things could potentially launch a new generation of air- and spacecraft like man has never seen.

Source: AGD impact magazine January 2010