Featured Research

from universities, journals, and other organizations

An evolutionary compromise for long tooth preservation

Date:
July 24, 2013
Source:
Max Planck Institute for Evolutionary Anthropology
Summary:
Researchers have conducted stress analyses on gorilla teeth of differing wear stages. Their findings show that different features of the occlusal surface antagonize tensile stresses in the tooth to tooth contact during the chewing process. They further show that tooth wear, with its loss of dental tissue and reduction of occlusal relief decreases tensile stresses in the tooth. The result, however, is that food processing becomes less effective. Thus, when the condition of the occlusal surface changes during an individual’s lifetime due to tooth wear, the biomechanical requirements on the existing dental material change as well -- an evolutionary compromise for longer tooth preservation.

Maximal principal stress distribution observed in three gorilla teeth of an unworn (left), a slightly worn (middle) and a worn (right) condition. (Source: Max Planck Institute for Evolutionary Anthropology))

Researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and the Senckenberg Research Institute in Frankfurt am Main, Germany, have conducted stress analyses on gorilla teeth of differing wear stages. Their findings show that different features of the occlusal surface antagonize tensile stresses in the tooth to tooth contact during the chewing process. They further show that tooth wear, with its loss of dental tissue and reduction of occlusal relief decreases tensile stresses in the tooth. The result, however, is that food processing becomes less effective. Thus, when the condition of the occlusal surface changes during an individual's lifetime due to tooth wear, the biomechanical requirements on the existing dental material change as well -- an evolutionary compromise for longer tooth preservation.

First, the researchers created 3D digital models of three gorilla lower second molars differing in wear stages. In a second step they applied a Software tool (Occlusal Fingerprint Analyser), developed in the Senckenberg Research Institute, to precisely determine tooth to tooth contacts. They then used an engineering approach, finite element analysis (FEA), to evaluate whether some dental traits usually found in hominin and extant great ape molars have important biomechanical implications.

The results show that in unworn and slightly worn molars (with a well-formed occlusal relief that is most effective for processing food) tensile stresses concentrate in the grooves of the occlusal surface. In such a condition, the different crests of a molar carry out important biomechanical functions, for example by reinforcing the crown against stresses that occur during the chewing process. Due to a loss of tooth tissue and a reduction of the occlusal relief the functionality of these crests diminishes during an individual's lifetime. However, this reduced functionality of the crests in worn teeth is counterbalanced by an increase in contact areas during tooth to tooth contacts, which ultimately contributes to a dispersion of the forces that affect the occlusal surface.

This suggests that the wear process might have a crucial influence in the evolution and structural adaptation of molars, enabling to endure bite forces and to reduce tooth failure throughout the lifetime of an individual. "It seems that we observe an evolutionary compromise for long tooth preservation. Even though worn teeth are not as efficient, they still fulfill their task. This would not be the case if they were lost prematurely," says Stefano Benazzi of the Max Planck Institute for Evolutionary Anthropology. He adds: "Tooth evolution and dental biomechanics can only be understood if we further investigate tooth function in respect to the dynamic changes of tooth structures during the lifespan of individuals."

"The results have strong implications for understanding the functional biomechanics of dental traits, for deciphering the evolutionary trend of our masticatory apparatus and might have important implications in modern dentistry for improving dental treatments," says Jean-Jacques Hublin, director of the Department of Human Evolution at the Max Planck Institute for Evolutionary Anthropology.


Story Source:

The above story is based on materials provided by Max Planck Institute for Evolutionary Anthropology. Note: Materials may be edited for content and length.


Journal Reference:

  1. Stefano Benazzi, Huynh Nhu Nguyen, Ottmar Kullmer, Jean-Jacques Hublin. Unravelling the Functional Biomechanics of Dental Features and Tooth Wear. PLoS ONE, 2013; 8 (7): e69990 DOI: 10.1371/journal.pone.0069990

Cite This Page:

Max Planck Institute for Evolutionary Anthropology. "An evolutionary compromise for long tooth preservation." ScienceDaily. ScienceDaily, 24 July 2013. <www.sciencedaily.com/releases/2013/07/130724102625.htm>.
Max Planck Institute for Evolutionary Anthropology. (2013, July 24). An evolutionary compromise for long tooth preservation. ScienceDaily. Retrieved April 19, 2014 from www.sciencedaily.com/releases/2013/07/130724102625.htm
Max Planck Institute for Evolutionary Anthropology. "An evolutionary compromise for long tooth preservation." ScienceDaily. www.sciencedaily.com/releases/2013/07/130724102625.htm (accessed April 19, 2014).

Share This



More Plants & Animals News

Saturday, April 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Vermont Goat Meat Gives Refugees Taste of Home

Vermont Goat Meat Gives Refugees Taste of Home

AP (Apr. 18, 2014) Dairy farmers and ethnic groups in Vermont are both benefiting from a unique collaborative effort that's feeding a growing need for fresh and affordable goat meat. (April 18) Video provided by AP
Powered by NewsLook.com
Man Claims He Found Loch Ness Monster With... Apple Maps?

Man Claims He Found Loch Ness Monster With... Apple Maps?

Newsy (Apr. 18, 2014) Andy Dixon showed the Daily Mail a screenshot of what he believes to be the mythical beast swimming just below the lake's surface. Video provided by Newsy
Powered by NewsLook.com
First Ever 'Female Penis' Discovered In Animal Kingdom

First Ever 'Female Penis' Discovered In Animal Kingdom

Newsy (Apr. 18, 2014) Not only are these newly discovered bugs' sex organs reversed, but they also mate for up to 70 hours. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins