Ld acid etching / dental implant courses by Indian dental academy

Enamel Tufts Enamel tufts are hypo-mineralized structures of enamel rods and inter-rod substance that project between adjacent groups of enamel rods from the dentino-enamel junction (FIG. 12 and 13) these projections arise in the dentin, extend into the enamel in the direction of the long axis of the crown, and may play a role in the spread of dental caries. These regions are of high porosity, as they cut across the prism structure, in which crystals are small and dispersed and protein abundant (Orams et al 1976).

Enamel Lamellae They are thin leaf faults between enamel rod groups that extend from the enamel surface towards the dentino-enamel junction, sometimes extending into the dentin (FIG. 12). They contain mostly organic material, which is a weak area predisposing a tooth to the entry of bacteria and dental caries (FIG. 14).

Enamel Spindles Odontoblastic processes sometimes cross the dentino-enamel junction into the enamel; these are termed enamel spindles when their ends are thickened (FIG. 12). They may serve as pain receptors, there by explaining the enamel sensitivity experienced by some patients during tooth preparation (FIG. 15).

Incremental Lines of Enamel - Striae of Retzius Enamel rods are formed linearly by successive opposition of enamel in discrete increments (FIG. 16). The resulting variations in structure and mineralization are called the Incremental Striae of retzius and can be considered growth rings (FIG. 12).

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