Featured Research

from universities, journals, and other organizations

Particles of crystalline quartz wear away teeth

Date:
January 9, 2013
Source:
Max-Planck-Gesellschaft
Summary:
Dental microwear, the pattern of tiny marks on worn tooth surfaces, is an important basis for understanding the diets of fossil mammals, including those of our own lineage. Now nanoscale research has unraveled some of its causes.

Surface of a tooth, with two large scratches (dark blue lines) that have been caused by quartz particles.
Credit: Peter Lucas, Kuwait University

Dental microwear, the pattern of tiny marks on worn tooth surfaces, is an important basis for understanding the diets of fossil mammals, including those of our own lineage. Now nanoscale research by an international multidisciplinary group that included members of the Max Planck Institute for Evolutionary Anthropology in Leipzig has unraveled some of its causes. It turns out that quartz dust is the major culprit in wearing away tooth enamel.

Silica phytoliths, particles produced by plants, just rub enamel, and thus have a minor effect on its surface. The results suggest that scientists will have to revise what microwear can tell us about diets, and suggest that environmental factors like droughts and dust storms may have had a large effect on the longevity of teeth. In particular, East African hominins may have suffered during dust storms, particularly from particles carried in by seasonal winds from the Arabian peninsula.

New research published by the scientists in Leipzig suggests that the main cause of the physical wear of mammalian teeth is the extremely hard particles of crystalline quartz in soils in many parts of the world. To show this, single particles were mounted on flat-tipped titanium rods and slid over flat tooth enamel surfaces at known forces. Quartz particles could remove pieces of tooth enamel at extremely low forces, meaning that even during a single bite, these particles could abrade much of the surface of the tooth if they are present in numbers.

In contrast, fossilized plant remains, so-called phytoliths, indented the enamel under the same conditions, but without tissue removal. The effect of the considerably softer phytoliths is similar to that of a fingernail pressed against a softwood desk. This kind of mark, called a rubbing mark, is visible but purely cosmetic.

The Max Planck Institute's Amanda Henry provided the phytoliths for the study, and assisted in the interpretation. "This study suggests that phytoliths do affect teeth, but in a different manner than we previously thought," she says. A new theory of wear, developed by collaborator Tony Atkins from Reading in the UK, suggests exactly what geometrical and material conditions are required for abrasive versus rubbing contacts. "People have not realized the vital importance of factoring fracture toughness into wear analyses" says Prof. Atkins. Study leader and Kuwait University researcher Peter Lucas says "we think that we've gone a lot further with the analysis of microwear than previous investigations because we realized that to uncover the mechanisms that cause it, you need to go one level smaller -- to nanoscale. It is only then that the difference between relatively innocuous rubbing contacts and those that remove tooth tissues becomes clear." The team could distinguish between marks made by quartz dust, plant phytoliths, and also by enamel chips rubbing against larger pieces of enamel.


Story Source:

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


Journal Reference:

  1. P. W. Lucas, R. Omar, K. Al-Fadhalah, A. S. Almusallam, A. G. Henry, S. Michael, L. A. Thai, J. Watzke, D. S. Strait, A. G. Atkins. Mechanisms and causes of wear in tooth enamel: implications for hominin diets. Journal of The Royal Society Interface, 2013; 10 (80): 20120923 DOI: 10.1098/rsif.2012.0923

Cite This Page:

Max-Planck-Gesellschaft. "Particles of crystalline quartz wear away teeth." ScienceDaily. ScienceDaily, 9 January 2013. <www.sciencedaily.com/releases/2013/01/130109215257.htm>.
Max-Planck-Gesellschaft. (2013, January 9). Particles of crystalline quartz wear away teeth. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2013/01/130109215257.htm
Max-Planck-Gesellschaft. "Particles of crystalline quartz wear away teeth." ScienceDaily. www.sciencedaily.com/releases/2013/01/130109215257.htm (accessed July 25, 2014).

Share This




More Fossils & Ruins News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Did ISIS Destroy Jonah's Tomb?

Did ISIS Destroy Jonah's Tomb?

Newsy (July 25, 2014) Unverified footage posted to YouTube purportedly shows ISIS militants destroying a shrine widely believed to be the tomb of the prophet Jonah. Video provided by Newsy
Powered by NewsLook.com
Mobile App Gives Tour of Battle of Atlanta Sites

Mobile App Gives Tour of Battle of Atlanta Sites

AP (July 25, 2014) Emory University's Center for Digital Scholarship has launched a self-guided mobile tour app to coincide with the 150th anniversary of the Civil War's Battle of Atlanta. (July 25) Video provided by AP
Powered by NewsLook.com
Tyrannosaur Pack-Hunting Theory Aided By New Footprints

Tyrannosaur Pack-Hunting Theory Aided By New Footprints

Newsy (July 24, 2014) A new study claims a set of prehistoric T-Rex footprints supports the theory that the giant predators hunted in packs instead of alone. Video provided by Newsy
Powered by NewsLook.com
Mint Gives JFK Coin a Face-Lift

Mint Gives JFK Coin a Face-Lift

AP (July 24, 2014) The U.S. Mint has re-designed the John F. Kennedy half dollar coin to better match the former president's likeness. (July 24) Video provided by AP
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