ISSN:
1573-6865
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract During the ameloblast differentiation stages, variations in the composition of different elements in the enamel matrix occur. The stages are characterized by a certain composition of elements being transported to, or from, the sites of calcification, forming a number of elemental gradients between hard and soft tissues. Sprague--Dawley rat incisor fragments, harbouring secretory ameloblasts, were frozen in liquid nitrogen, dried by sublimation, embedded, ground cut and subjected to quantitative secondary ion mass spectrometry. In addition, rats were perfused with an aldehyde, after which the maxillary incisors were extracted, embedded, ground cut and subjected to secondary ion mass spectrometry imaging. The ion gradients of 12C, 19F, 23Na, 35Cl and 44Ca in the Tomes processes region--enamel matrix interface were mapped. The results showed steep elemental gradients between the Tomes processes region and the enamel matrix, demonstrating preserved barrier functions after fixation. The gradients of 12C, 19F, 23Na and 44Ca were maintained close to, or within, the Tomes processes. The data are in favour of a theory that the Tomes processes region--enamel matrix interface acts as a selectively permeable barrier. © 1998 Chapman & Hall
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1003284511863
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