New low-cost device to detect tooth cavities early

Scientists have developed a new low-cost, noninvasive imaging device that could enable dentists to detect and heal tooth cavities much earlier.
Dentists currently rely on two methods to detect early caries or tooth decay: X-ray imaging and visual inspection of the tooth surface.
However, both of these diagnostics have limitations: dentists can not see the cavity until it is relatively advanced, and X-rays ca not detect occlusal early caries - those on the biting surface of the tooth.
Now, researchers at York University in Toronto have described a new method enabling much earlier detection using inexpensive long-wavelength infrared imaging.
A cavity begins with a minute amount of mineral loss from the tooth enamel surface, resulting from the acidic environment of dental plaques.

If caries can be detected early enough, the progression can be stopped or even reversed.

The newly developed low-cost thermophotonic lock-in imaging (TPLI) tool would allow dentists to detect developing caries much earlier than X-rays or visual analysis.
The TPLI tool uses a long-wavelength infrared camera to detect the small amount of thermal infrared radiation emitted from dental caries after stimulation by a light source.
To test the effectiveness of this new imaging tool, researchers, Ashkan Ojaghi, Artur Parkhimchyk, and Nima Tabatabaei of York University, artificially induced early demineralisation on an extracted human molar by submerging it in an acid solution for two, four, six, eight and 10 days.

The TPLI image taken after just two days clearly showed the presence of a lesion, whereas a trained dental practitioner could not visually detect the same lesion even after 10 days of demineralisation.
The tool has the benefits of being non-contact, noninvasive, and low-cost and has great potential as a commercially viable diagnostic imaging device for dentistry, researchers said.
Dental caries - tooth decay - is the most prevalent dental disease among children and adults around the world.
Left too long before treatment, the disease results in difficulty eating, infection and even tooth loss.
The finding was published in the Journal of Biomedical Optics.