Fine structure of the human secretory ameloblast.

The fine structure of secretory ameloblasts in primary tooth germs from a human fetus was investigated. Various aldehyde fixatives produced varying qualities of preservation. The morphology of the best preserved ameloblasts differed from that earlier described, mainly in the following respects: the rough endoplasmic cisternae were lamellated and regularly arranged, the mitochondria were of regular shape and size, and the ground substance was dense and homogenous. The extensive Golgi complexes, the mitochondria and the rough endoplasmic cisternae in the apical (distal) part of the ameloblast were longitudinally arranged.