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 Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View
22.06.2018 | University of Sussex

nachricht New cellular pathway helps explain how inflammation leads to artery disease
22.06.2018 | Cedars-Sinai Medical Center

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Superconducting vortices quantize ordinary metal

Russian researchers together with their French colleagues discovered that a genuine feature of superconductors -- quantum Abrikosov vortices of supercurrent -- can also exist in an ordinary nonsuperconducting metal put into contact with a superconductor. The observation of these vortices provides direct evidence of induced quantum coherence. The pioneering experimental observation was supported by a first-ever numerical model that describes the induced vortices in finer detail.

These fundamental results, published in the journal Nature Communications, enable a better understanding and description of the processes occurring at the...

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Rapid water formation in diffuse interstellar clouds

25.06.2018 | Physics and Astronomy

Using tree-fall patterns to calculate tornado wind speed

25.06.2018 | Earth Sciences

'Stealth' material hides hot objects from infrared eyes

25.06.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>