*3.2.2.5.2 Optical coherence tomography (OCT)*

It is a novel, non-irradiative, non-invasive imaging technique. The concept of OCT is based on the differences in the optical absorption and scattering properties of the dental tissue. It uses infrared light to produce a real-time cross-sectional image of dental tissue. Demineralized tissue can be distinguished from sound tissue based on the following principles:


Enamel caries appear brighter on grayscale OCT images whereas dentin caries gives the image a continuous bright area throughout the enamel into the dentin [26].
