Scientists have invented a new product that can encourage tooth enamel to grow back, which means we could finally have a game-changing way to treat dental cavities. It is based on peptides - short chains of amino acids, linked by peptide bonds, that aren't long enough to be considered full proteins.

It is produced by a type of cell called an ameloblast. These secrete the proteins that form enamel while the tooth is still in the gum. Unfortunately, once the process of forming tooth enamel is complete and the tooth has emerged, our ameloblasts die off. But we continue to lose enamel throughout our lifetime.

To a small extent, our teeth can bed with the help remineralise of saliva, fluoride toothpaste and drinking water additives. But once there's a visible cavity on the tooth, it needs to be treated by a dentist - which usually means drilling, and packing the hole with a dental filling. To develop their new treatment, the team turned to one of the proteins produced by ameloblasts. 

They applied it to dental lesions in a laboratory setting and found that it helped form a new mineralised layer to the demineralised areas, integrating it with the enamel underneath. They also treated similar lesions with fluoride, but only the peptide treatment resulted in the remineralisation of a relatively thick layer - resembling the structure of healthy enamel.