The protective layer of fluoride, which is formed on the teeth thanks to treatments with the use of various preparations, is even a hundred times thinner than previously thought. Having found this, scientists are wondering whether the compounds of this fluoride, previously considered an effective treatment against caries, protect teeth at all, says Langmuir.
Caries is one of the most common health problems in the world. In the United States alone, citizens spend over $ 50 billion each year treating tooth holes. Adding fluoride to toothpastes, mouthwashes and municipal drinking water has been identified as one of the most effective ways to prevent tooth decay.
Scientists have long accepted that fluoride strengthens enamel – the hard substance that covers the surface of teeth – making it more resistant to the processes involved in the formation of caries. Some thought that thanks to the addition of fluoride, the main mineral in enamel, hydroxyapatite, turns into a more resistant material called fluorapatite.
However, new research by Frank Mueller from Saarland University in Saarbrcken, Germany, has shown that the layer of fluorapatite that forms in this way is only six nanometers thick. To obtain the thickness of the diameter of a human hair, you need to overlap almost 10. such layers.
Previously, scientists estimated that this protective layer had a thickness of at least ten times as thick. Today they wonder if a layer so thin that it can be rubbed off simply by chewing food is actually a barrier to tooth decay. They also ask whether fluoride has an impact on enamel that they did not know about – this issue may be clarified by further studies. (PAP)