Take a fresh look at your lifestyle.

The first map of human enamel shows how cavities form and can help dentists REVERSE tooth decay

The first atomic-scale map of human enamel helps reveal how cavities form – and may even help experts reverse tooth decay, researchers say.

It has been prepared using a combination of advanced scanning techniques and chemical analysis, revealing the structural composition of the enamel in unprecedented detail.

Enamel is the outer protective layer on our teeth – covering the entire crown – and has a considerable hardness thanks to its high mineral content.

Researchers from the US found that the internal structure of the smallest parts of frosting resembles ‘the smallest sandwich in the world,’ with a more soluble core.

The findings may help pave the way for methods of making enamel harder – the end of both fillings and the dentist’s dreaded drill.

Scroll down for video

The first atomic-scale map of human enamel helps reveal how cavities form - and can even help experts reverse tooth decay, researchers claim (stock image)

The first atomic-scale map of human enamel helps reveal how cavities form – and can even help experts reverse tooth decay, researchers claim (stock image)

“Enamel has evolved to be tough and hard-wearing enough to withstand the forces associated with chewing for decades,” said paper author and materials scientist Derk Joester of Northwestern University in Illinois.

However, enamel has very limited regeneration potential. Our fundamental research helps us understand how enamel can form, which should help develop new interventions and materials to prevent and treat caries. ‘

Caries, commonly known as tooth decay, is formed when teeth are broken down by bacteria. They are often treated by replacing the decayed area with a filling – after this, of course, has been removed by the dreaded dental drill.

Fillings have been a mainstay of dental repair for over 200 years – and it is estimated that the average Briton has as many as seven fillings.

Despite their common usage, the ‘holy grail’ of dental care continues to find a way to tackle tooth decay without resorting to drill bits and fillings.

“This work provides much more detailed information about the atomic composition of enamel than we previously knew,” said paper author Jason Wan of the National Institute of Dental and Craniofacial Research in Maryland.

“These findings can expand our thinking and our approach to strengthening teeth against mechanical forces and repair damage from erosion and decay.”

In their study, the researchers identified the chemicals that contribute to the strength of the enamel, while at the same time making the core more soluble and more vulnerable to erosion.

“The ability to visualize chemical gradients down to the nanoscale increases our understanding of how enamel can originate and could lead to new methods of improving enamel health,” said paper author and materials scientist Paul Smeets.

The enamel can reach a thickness of a few millimeters and first consists of a three-dimensional fabric of bars. Each of these – about 5 microns wide, or one-fifteenth the width of a human hair – is made up of thousands of individual long and thin “crystallites” of a mineral known as hydroxylapatite. Depicted, the individual crystallites that make up the glaze

A major obstacle that has hindered glaze research is its complex structure – because it has different characteristics that occur on different scales.

The enamel can reach a thickness of a few millimeters and first consists of a three-dimensional fabric of bars.

Each of these – about 5 microns wide, or one-fifteenth the width of a human hair – is made up of thousands of individual long and thin “crystallites” of a mineral known as hydroxylapatite.

Each crystallite, in turn, is several tens of gauges thick – and these are the basic building blocks of the glaze.

Each crystallite has a continuous crystal structure, with periodic arrangements of calcium, phosphate and hydroxyl ions.  In the center, however, these are replaced with magnesium, sodium, carbonate, and fluoride - with each core containing two magnesium-rich layers that flank a mix of sodium, fluoride, and carbonate ions.  The photo shows the dark deformations in these crystallite magnesium impurities in the glaze

Each crystallite has a continuous crystal structure, with periodic arrangements of calcium, phosphate and hydroxyl ions.  In the center, however, these are replaced with magnesium, sodium, carbonate, and fluoride - with each core containing two magnesium-rich layers that flank a mix of sodium, fluoride, and carbonate ions.  The photo shows the dark deformations in these crystallite magnesium impurities in the glaze

Each crystallite has a continuous crystal structure, with periodic arrangements of calcium, phosphate and hydroxyl ions.  In the center, however, these are replaced with magnesium, sodium, carbonate, and fluoride - with each core containing two magnesium-rich layers that flank a mix of sodium, fluoride, and carbonate ions.  The photo shows the dark deformations in these crystallite magnesium impurities in the glaze

Each crystallite has a continuous crystal structure, with periodic arrangements of calcium, phosphate and hydroxyl ions.  In the center, however, these are replaced with magnesium, sodium, carbonate, and fluoride - with each core containing two magnesium-rich layers that flank a mix of sodium, fluoride, and carbonate ions.  The photo shows the dark deformations in these crystallite magnesium impurities in the glaze

Each crystallite has a continuous crystal structure, with periodic arrangements of calcium, phosphate and hydroxyl ions. In the center, however, these are replaced with magnesium, sodium, carbonate, and fluoride – with each core containing two magnesium-rich layers that flank a mix of sodium, fluoride, and carbonate ions. The photo shows the dark deformations in these crystallite magnesium impurities in the glaze

Using a combination of advanced microscopy and chemical detection techniques, the researchers revealed that each crystallite has a shell and a core.

In addition, each crystallite has a continuous crystal structure, with periodic arrangements of calcium, phosphate and hydroxyl ions.

In the center, however, these are replaced with magnesium, sodium, carbonate, and fluoride – with each core containing two magnesium-rich layers that flank a mix of sodium, fluoride, and carbonate ions.

“Surprisingly, the magnesium ions form two layers on either side of the core, like the world’s smallest sandwich – just 6 billionths of a meter wide,” says paper author and materials scientist Karen DeRocher, also of Northwestern University.

The center of each crystallite appears to be more soluble than the edges, Professor Joester noted – although this phenomenon may be unique to human enamel.

“Surprisingly, the magnesium ions form two layers on either side of the core, like the world’s smallest sandwich – just 6 billionths of a meter wide,” says paper author and materials scientist Karen DeRocher, also of Northwestern University. Depicted tomography images of the nuclear probe from the same set of crystallites. Each colored dot represents a single atom

Tooth decay is one of the world’s most common chronic diseases – it affects up to 90 percent of children and the vast majority of adults, according to the World Health Organization.

It is estimated that the NHS delivers about seven million refills in England alone each year – for around £ 3.4 billion.

If tooth decay is left untreated, it can lead to painful abscesses, bone inflammation or loss.

“This new information will allow a model-based simulation of enamel breakdown that was previously not possible, allowing us to better understand how caries develop,” explains Ms. DeRocher.

The full findings of the study are published in the journal Nature.

.