The Canary System has been approved for sale in the US. It is an amazing device to detect caries that uses a completely different technology than previous devices. I have been watching the development of the system for some time and am excited to see it is now available in the US. The following comes directly from The Canary web site.
The Canary System™ is a device for the early detection and monitoring of tooth decay. It can detect decay on smooth enamel surfaces, root surfaces, biting surfaces, between teeth and around existing amalgam or composite fillings. It is a pain-free, safe and non-invasive early detection system built on years of thorough research.
How does The Canary System work?
The Canary uses a low-power, pulsating laser light to scan teeth for the presence of dental caries or tooth decay. The laser light is absorbed by the tooth and two phenomena are observed: the laser light is converted into luminescence and there is a release of heat. This heat will not harm the tooth but gives us important information about the tooth up to a depth of 5 mm below the surface. Simultaneous measurement of the reflected heat and light provides us with information on the presence and extent of tooth decay below the tooth surface before being detected by dental radiographs.
via The Canary System.