Enamel spindles

Enamel Spindles are formed when odontoblast processes crosses the dentinoenamel junction and reach the enamel which are thickened at their end. They seem to originate from processes of odontoblasts that extended into the enamel epithelium before hard substances were formed. The direction of the odontoblast processes and spindles in the enamel corresponds to the original direction of the ameloblasts at right angles to the surface of the dentin. Since the enamel rods are formed at an angle to the axis of the ameloblasts, the direction of spindles and rods is divergent.

In ground sections of dried teeth the organic content of the spindles disintegrates and is replaced by air, and the spaces appear dark in transmitted light. TEM studies showed spindles to be channels of about 2 microns in diameter containing small needle-like crystals of about 70 nm in length and about 5 nm in width, or granular and/or amorphous material.

The structure of the spindles were similar to enamel tufts and that both of them were hypomineralized or partially mineralized structures. They are found mainly in the cup tip regions. Energy dispersive X-ray microscopy showed that enamel tufts, lamellae and spindles contained less calcium and phosphorus than enamel prisms.

Enamel spindles Resources
Latest articles Most recent articles Ongoing trials	Wikipedia