Health

Have scientists discovered the perfect way to repair rotten teeth?

Enamel is the hardest substance in our bodies, and scientists are working out how to grow it in a lab. It could transform dentistry, says Lucy Stock of Gentle Dental Care

The enamel on our teeth is the hardest substance in the body, harder than steel
The enamel on our teeth is the hardest substance in the body, harder than steel The enamel on our teeth is the hardest substance in the body, harder than steel

It's a 'spill your tea' moment – and you didn't even feel a thing. Scientists have for the very first time grown tooth enamel in the lab.

"This may finally be the 'century of living fillings' and human regenerative dentistry in general," said lead researcher Hannele Ruohola-Baker, professor of biochemistry and associate director of the UW Medicine Institute for Stem Cell and Regenerative Medicine, as published in the journal, Developmental Cell.

Enamel is the hardest substance in the body, harder than steel, which is amazing considering it's made from the same substance that pain-grating kidney stones consist of, calcium phosphate.

Each minute calcium phosphate enamel crystal is one-thousandth the width of a human hair. On its own, an enamel crystal would be incredibly weak, just like a single fibre of rope which only gains strength when wound together.

The microscope reveals the delightful interlinking flowing, ribbon pattern of enamel crystals which gives enamel its strength to protect the vulnerable innards of a tooth.

Even though enamel lacks blood vessels, it doesn't act like a 'dead' entity. Enamel has minuscule pores all over its surface, so a tooth is in a continual state of flux with chemical substances entering or leaving it depending on whether and what we have just eaten.

Our amazing teeth took an awfully long time to reach fruition. Half a billion years ago the first vertebrates were jawless fish with simple tooth-like structures deep down in their mouths. Over many millennia, teeth in all their varieties, started to appear in animals and humans.

So, it's even more amazing then, that Prof Ruohola-Baker and her team were able to coax stem cells using almost as much painstaking tenacity as it takes to get teenagers to clean their bedrooms, to eventually make teeny tiny three-dimensional micro-organs called organoids.

These organoids were subsequently used to produce the three main proteins of enamel: ameloblastin, amelogenin and enamelin. The proteins were then combined into a matrix which mineralises into lab-made enamel.

This is the beginning of scientists working out how to bioengineer enamel into a usable form, possibly 3D printed into shapes, that could be adapted by dentists to rebuild rotten teeth.

One would imagine that this would transform dentistry for patients – the ultimate filling material.