Optical Coherence Tomography in Dentistry

Optical Coherence Tomography is an imaging technique characterized by high spatial resolution and noninvasive subsurface detection1. OCT started as an interferometric technique utilizing the newly emerged low coherence or partial coherence light source and time-domain gating to achieve the depth resolution. With additional lateral scans, 2-D or 3D tomographic images can be obtained. The instrumental development of OCT has experienced several phases. It goes from free space architectures to fiber-based systems, from intensity-based structural imaging to multiple functional extensions of polarization sensitive, Doppler, and spectroscopic OCT. Since the beginning of this century, a Fourier domain OCT infrastructure has been introduced that resulted in a new revolution in OCT technology2, 3. Not only was the new technology bringing a hundred times more sensitivity, it was also technically more convenient for the design of a higher speed scanning system structures. Nowadays, FD-OCT are implemented with either a spectrometer or a tunable laser design. Modern OCT is more accurately defined as a broadband rather than lowcoherence interferometric technology. And the outcome is a true 3D imaging modality4-9 with high data speed for real-time clinical diagnosis, free from the degradation of motion artifacts.