Microchannels in the surface zone of artificially produced caries-like enamel lesions

In the surfaces zones of artificial carious lesions, tiny microchannels, about 0.5 - 1.5 micrometers in diameter and roughly 100 micrometers in length, have been observed. The mineral components seem to be concentrated at the lumen borders, whereas the organic components have disappeared or are disorganized. These observations suggest that the channels mentioned are involved in the lesion development and play an important role in diffusion (transport) processes taking place between the sub-surface lesion and the liquid phase outside the lesion. The microchannels originate in prisms in the perikymata of the surface enamel. They extend in the direction of the Hunter-Schreger bands, mainly in connection with diazones. No relationship could be found between the microchannels and the direction of the prism sheaths. This indicates that in initial artificial lesion formation the enamel structure plays an important role.