Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Shark teeth are not harder than human teeth

30.07.2012
Scientists at the University of Duisburg-Essen (UDE) and the Max-Planck-Institut für Eisenforschung (MPIE) in Düsseldorf have analyzed the structure of shark teeth and human teeth.
The results of this research project are surprising: Although shark teeth contain 100% of a fluoride (i.e. the mineral which is also present in low concentrations in toothpastes), they are not harder than our teeth.

It is not by coincidence that the material and nano scientists have analyzed shark teeth. "I had wanted to do this for a long time", underlined Matthias Epple, Professor for Inorganic Chemistry. "We have been investigating biomineralization at the UDE for several years. It is our main goal to determine the effect of inorganic minerals on biological systems, such as teeth, bones and seashells.

It is well-known that sharks have enamel which consists of the very hard mineral fluoroapatite. So far, no scientist has investigated this with high-end chemical and physical methods." This was now done by Epple and his colleague from the MPIE Professor Dierk Raabe, together with Dr Oleg Prymak and Joachim Enax. The main part of the work was carried out at UDE. The MPIE was the institute, where especially the mechanical measurements took place.

For this study the teeth of shortfin mako shark and tiger shark were literally "taken apart" – for these shark species have different habits of eating their prey. By scanning electron microscopy and X-ray diffraction, the scientists analyzed the order, the size and the nature of the fluoroapatite crystals and determined the hardness of the teeth locally in small areas with mechanical measurements.

Epple and his co-workers showed that the chemical and crystallographic composition of teeth is similar in different shark species, although mako sharks "tear" into the flesh of their prey while tiger sharks "cut" it. The interior consists of the more elastic dentin; the outer part is the highly mineralized enamel.

Thus one might suppose that shark teeth are harder than human teeth. "The human enamel consists of a little softer mineral, hydroxyapatite, which is incidentally also present in bones." By carrying out a comparative study with a human tooth, the scientists discovered something surprisingly new: It is just as robust as that of that fearful animal. "This is due to the special micro- and nanostructure of our teeth.

The crystals in human teeth have a special arrangement and they are "glued together" by proteins, which stops cracks from running through the whole tooth", said Epple, who is also a member of the Center for Nanointegration Duisburg-Essen (CENIDE). Incidentally nature has equipped all creatures similarly: If teeth were fully mineralized they would be in danger of cracking upon mechanical shock.

The scientists are now continuing their research on shark teeth, e.g. on sharks of different age. With their experiments they are trying to imitate these structures to lay the foundations for novel dental prostheses. "It would be great if – sometime in the future - one could repair teeth with a material, which is more natural than today`s provisional solutions."

Until then, humans will have to accept that sharks still have better teeth: They are replaced continuously and do not develop any cavities. "The reason might be the fluoroapatite and the revolving set of teeth which is always immersed in sea water", explained Matthias Epple. "And finally: Sharks do not eat sugar."

The research findings are published in the recent issue of the Journal of Structural Biology, 178 (2012). DOI http://dx.doi.org/10.1016/j.jsb.2012.03.012.

Further information: Prof. Dr. Matthias Epple, University of Duisburg-Essen, +49 0201/183-2413, matthias.epple@uni-due.de

Note for editorial staff: Prof. Epple will be out of office until August, 20th. The university press office can contact him. Please write to Ms. Ulrike Bohnsack, ulrike.bohnsack@uni-due.de

Ulrike Bohnsack | idw
Further information:
http://www.uni-due.de

More articles from Life Sciences:

nachricht Multifunctional Platform for the Delivery of Gene Therapeutics
22.01.2018 | Angewandte Chemie International Edition

nachricht Charge Order and Electron Localization in a Molecule-Based Solid
22.01.2018 | Max-Planck-Institut für Chemische Physik fester Stoffe

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

The world's most powerful acoustic tractor beam could pave the way for levitating humans

22.01.2018 | Power and Electrical Engineering

Siberian scientists learned how to reduce harmful emissions from HPPs

22.01.2018 | Power and Electrical Engineering

Combination of Resistance Genes Offers Better Protection for Wheat against Powdery Mildew

22.01.2018 | Agricultural and Forestry Science

VideoLinks
B2B-VideoLinks
More VideoLinks >>>