Page 73 - My FlipBook

Fig. 29. A photomicrograph from a portion of a mesio-distal section of a first molar show-
ing in the section two zones of interglobular spaces.
It shows only a part of the mesial half of
the section Note that the line of interglobular spaces nearest the enamel, the first line, follows
closely the dento-enamel junction.
This follows the prominence of the mesial marginal ridge of
dentin (on the left in the picture) and then dips down to the gingival.
The line of injury to
tne enamel also rounds over this prominence and again touches the dentin just above the point
of ending of the injury to the dentin.
The second, and more marked zone of injury to the
dentin, swings out quickly from the dento-enamel junction, on the left in the picture, and runs
across much deeper in the tooth, showing the amount of dentin formed before this occurred.