Humans have two sets of teeth in a lifetime, the baby teeth and the permanent “adult” teeth.
Teeth are the hardest bones in the body, but tooth decay and acids found in our food and drinks lead to loss of tooth enamel, which is the mineralized substance protecting their surface.
When generated, the cells that produce enamel die instantly, and it erodes, breaks, or chips, and can never regenerate itself again.
However, Chinese scientists have created a liquid solution able to grow back the tough external surface of damaged tooth enamel by using a material that mimics the natural mineralization process of the protective outer layer of the teeth.
This new gel actually makes enamel repair itself, as the method replicates the biomineralization process whereby cells known as ameloblasts release proteins that eventually become enamel.
However, ameloblasts are only present during tooth development, so our mature teeth have virtually no natural ability to self-repair after they have formed.
Namely, researchers from Zhejiang University School of Medicine in China combined the two minerals found in enamel, calcium and phosphate ions, and developed an alcoholic solution with the organic compound trimethylamine.
The new technique required a new kind of calcium phosphate ion clusters (CPICs), measuring just 1.5 nanometres in diameter. The tiny particles were later stabilized in an ethanol solution with a chemical called triethylamine, which prevents them from clumping together.
When researchers applied the gel-like material to human teeth donated by patients, in a simulated mouth-like environment, the ultra-small clusters successfully fused to the fish-scale-like structure of native enamel, replicating the coating of the tooth with an indistinguishable and equally hard repair layer that developed to a thickness of up to 2.8 micrometers within 48 hours.
The complex, crystalline nature of enamel has been the reason for numerous failed attempts before, so this technique is billed as a world-first.
Globally, the dental community is very excited about this research, as current dentist-recommended products repair enamel but are not able to regrow the complex crystal structure to recreate a pearly white shimmer.
Researchers explained their rationally designed material composed of calcium phosphate ion clusters can be used to produce a precursor layer to induce the epitaxial crystal growth of enamel apatite, which mimics the biomineralization crystalline-amorphous frontier of hard tissue development in nature.
Also, according to biomimetics and material scientist Zhaoming Liu, a co-author of the study, the newly regenerated enamel has the same structure and similar mechanical properties as native enamel.
Yet, as the study has only been performed on extracted teeth, the team of researchers plans to test their method on mice, and then people soon after.
They hope they can regrow tooth enamel without using fillings which contain totally different materials, and if everything goes well, to start trials in people within the next few years.
The significance of the new technique is that it could potentially repair decayed teeth and prevent tooth decay for good!
Experts believe it could be several years before this material finds its way into clinical use at our local dentists, provided future tests indicate it’s both safe and effective.
Therefore, Chen Haifeng, an associate professor at Peking University’s biomedical engineering department, advises that until the new material is entirely tested, we should still be careful about our dental health.
He adds that we should never wait for the damage to happen, as prevention is the best approach.
“Our teeth are a miracle of nature. Artificial replacement will never do the job as well.”