Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fast toothpaste check

10.10.2012
There are various types of toothpaste available on the market. They come as pastes and gels, there are some that guard against tooth decay or protect teeth from acid attack, others that are designed for sensitive teeth. But which toothpastes clean well? Which preserve the tooth enamel? A new evaluation method sheds light on the subject.

Everyone wants to have beautiful teeth. After all, a perfect set of teeth symbolizes health and youthfulness, and can even influence career prospects. If having pristine teeth calls for thorough oral hygiene, then how well or badly does a given toothpaste clean? How effective is it? What should it contain in order not to damage the structure of the teeth?


Researchers intend to supplement their microtribological analyses of the interaction between toothbrush, toothpaste and tooth surface with practical tests, using a tooth cleaning machine they have developed themselves. Bottom right: Friction and wear tests with individual bristles. © Fraunhofer IWM

Such questions are primarily of interest to manufacturers of dental hygiene products, and answers are being delivered by researchers from the Fraunhofer Institute for Mechanics of Materials IWM in Halle. Through close collaboration with the Microtribology Centre µTC in Karlsruhe they have developed a new process for testing the abrasive effect of toothpastes, allowing this ‘abrasivity’, as experts call it, to be compared and evaluated in the lab.

Dangerous abrasive effect

Cleaning particles are an important component of toothpastes. These abrasives, as they are known, mechanically remove dental plaque. Nevertheless, the paste should not be too strongly abrasive. Over the years the abrasion can cause damage to the tooth enamel, which does not regenerate itself. This damage is more visible and pronounced in the soft dentin. The German Dental Association recommends that people choose less abrasive toothpaste if the necks of their teeth are exposed.

The abrasive effect of a particular toothpaste on tooth dentin depends on the hardness, amount and particle size of the abrasive additives it contains, such as silica or alumina. Abrasivity is measured as the RDA value (radioactive dentin abrasion), ranging from 30 to over 200. This value is determined via a complex process that involves testers brushing over radioactively marked dentin samples. The abraded material is then measured via the resultant radiation intensity of the toothpaste slurry. Not all experts agree on the validity of RDA values, as test results have been known to vary partly from lab to lab.

Determining abrasion rates with microtribological tests

The researchers at the IWM have chosen an alternative method to this radiotracer system. “Our new approach enables us to determine realistic abrasion rates and characterize the interaction between brush, enamel and toothpaste. What’s more, our tests are less laborious than the time-intensive radiotracer procedures carried out by only a handful of laboratories worldwide”, says Dr. Andreas Kiesow, team leader at the IWM. The scientist and his team have successfully managed to determine the abrasion of various toothpastes on a microscopic scale and to measure the friction values using microtribological experiments. “Until now, tribological values such as friction coefficient, did not exist” says Kiesow.

The researchers use human teeth as well as different toothpastes made by industrial partners for their experiments. These toothpastes were diluted with water and saliva in order to create a solution whose consistency corresponds to the mixture of toothpaste and saliva that is present when people brush their teeth. The friction and wear tests were each carried out with a single bristle – referred to as a monofilament. This is mounted in specialized tribological instruments, a microtribometer and a nanoindenter, and moved over the sample in both straight and circular motions, in the latter case up to 8000 times. Highly sensitive instruments then measure the depth of the resultant marks left on the surface of the tooth. “Our findings reveal that the RDA value of toothpastes correlates with the depth of abrasion; the higher the value, the greater the abrasion. By analyzing the friction value we also identified a clear relationship between the friction behaviors of the bristle on the dental enamel and the abrasiveness of the toothpaste”, sums up Kiesow. The new process allows the researchers to not only characterize the abrasion more quickly and simply, but also to describe how different geometries of toothbrush filaments act upon the surface of the tooth and how the bristle shape should ideally be designed. The experts at IWM can use their know how to support manufacturers of dental hygiene with product development. At the end of the day it is the consumer who benefits most.

Dr. Andreas Kiesow | Fraunhofer Research News
Further information:
http://www.fraunhofer.de/en/press/research-news/2012/october/fast-toothpaste-check.html

More articles from Life Sciences:

nachricht The birth of a new protein
20.10.2017 | University of Arizona

nachricht Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>