ISSN:
1432-0827
Keywords:
Radioautography
;
Mineralization
;
Incisors
;
Odontoblasts
;
Ameloblasts
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
,
Physics
Notes:
Abstract To find out whether the calcium phosphate of dentin and enamel is elaborated in the cells prior to passing into the organic matrix or is initially deposited into the matrix, rats were injected intravenously with45Ca and killed 30 sec or 5 min later by glutaraldehyde perfusion; semithin sections of the undecalcified incisor teeth were then radioautographed for detection of the incorporated45Ca. Rat incisor teeth were selected since there is evidence that the calcium they take up is “stable”; that is, not subject to significant loss by exchange or by other physiocochemical processes. Whendentin is examined after45Ca injection, the maximum radioautographic reaction is observed next to the junction with predentin and a gradual decrease up to the dentin enamel border. No radioactivity is detected in odontoblasts. These observations are interpreted as indicating that the initial site of calcium phosphate deposition is in the matrix of dentin. In theenamel, the radioautographic reaction is spread fairly uniformly throughout the matrix, with a weak reaction over ameloblasts attributed to radiation scatter. The interpretation is again that calcium phosphate is deposited into the matrix; and, furthermore, that this deposition begins as soon as the matrix is laid down and continues at about the same rate up to an advanced stage of mineralization.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02059059
