Scientists in the UK have developed a new material that can be inserted into teeth to repair and regenerate dentin - the hard, bone-like tissue that makes up the bulk of all teeth.

Just like regular fillings, which are inserted into a tooth to block off spaces where bacteria could colonise, the new material is injected into the tooth and hardened with UV light. But once inside the pulp of the tooth, it actually encourages stem cells to proliferate and grow into dentin.

"We have designed synthetic biomaterials that can be used similarly to dental fillings but can be placed in direct contact with pulp tissue to stimulate the native stem cell population for repair and regeneration of pulp tissue and the surrounding dentin," says lead researcher Adam Celiz, a therapeutic biomaterials researcher from the University of Nottingham.

The technique just won second prize in the materials category of the UK Royal Society of Chemistry's Emerging Technologies Competition 2016, and while there's not a whole lot of information available about how it actually works, it appears to be a new form of 'pulp capping'.

Pulp capping is a technique dentists use to try and stop dental pulp from dying. Pulp is one of the four major components of teeth, along with enamel, dentin, and cementum. 

The surface enamel is the hardest layer, and under that is the second hardest layer, dentin. Dentin is important because it surrounds and connects to the pulp of the tooth, which is made up of living connective tissue and cells called odontoblasts, and found in the middle of your tooth. 

The pulp is where your blood vessels, nerves, and connective tissue are found, so you really don't want to mess that up.

Problems start when you get a cavity that eats away your enamel, dentin and cementum - a calcified substance covering the root of a tooth - and exposes the pulp. If dentists don't get in there fast enough with a protective pulp-capping substance (or if the procedure fails), you're looking at an expensive and painful root canal treatment. (Nooooo.)

Right now, pulp capping materials are usually made of materials such as calcium hydroxide or Mineral trioxide aggregate (MTA), and they don't do anything other than protect, and around 10 to 15 percent of these fillings fail.

That's where the University of Nottingham's invention comes in. Their new pulp capping material is designed to stop pulp capping failure by encouraging the growth of more natural dentin to protect it.

As Coby McDonald reports for Popular Science: 

"In in vitro testing, the fillings stimulated the proliferation and differentiation of stem cells into dentin, the bony tissue that forms the bulk of the tooth under the white enamel. 

The researchers believe that if used in a damaged tooth, those stem cells can repair the kind of damage that often comes from the installation of a filling. In essence, the biomaterial filling would allow the tooth to heal itself."

As mentioned earlier, the team hasn't released a lot of information about their new material, and have yet to publish it in a peer-reviewed journal, so we'll have to be cautiously optimistic about it for now until we can see more information about exactly how it works, and how expensive it will be.

But if it can save some poor souls from having to get root canal - or even worse, having to lose the tooth altogether - this could be a very, very good thing.