Microradiographic and polarized light study of red deer root dentin with special reference to occurrence of giant tubules.

Radiolucent bands following the course of the dentinal tubules were observed in sections of undemineralized roots of permanent red deer incisors. Some of these bands, previously unreported in mammalian root dentin, contained giant tubules similar to those described earlier by the author in the coronal dentin of this animal. The root giant tubules initiated with funnel-shaped orifices at the border of the pulpal cavity and, generally, terminated in the peripheral dentin, whereas a few penetrated into the cementum. Whether the giant tubules should be considered to be anomalous dentinal tubules or a different type of structure could not be determined. The distinction between root giant tubules and accessory canals being part of the apical ramification did not represent any problem.