This technology is still in the testing stage. Current estimates are that we will see it available for clinical use in 2011. Check out the videos under OCT in dentistry.
Optical Coherence Tomography OCT is generally regarded as the 6th Imaging Modality and is a new, light-based system with characteristics that make it ideally suited to bio-medical diagnostic imaging applications. OCT represents a major advancement in imaging in dentistry due its ability to provide detailed characterization of the dental microstructures, enabling the dentist to make earlier and more accurate diagnosis of oral disease including decay and periodontal disease.
via Lantis Laser, Inc..