31. •
The lamellar appearance of the cellular cementum is
apparent, as are the cemento cytes. A hyaline layer
(green arrow) lies between the cementum and dentin,
and contains proteins secreted by the root sheath that
are related to the enamelins produced by the
ameloblasts. In addition, the collagen fibers of primary
acellular cementum are oriented perpendicularly to
the fibers of the dentin into which they insert. This
provides for the very strong bonding of cementum to
dentin, and thus aids in the attachment of the tooth to
alveolar bone via the periodontal ligament fibers. The
tubular structure of dentin is clearly visible, and the
granular layer of Tomes (black arrow) can be seen
subjacent to the cementum
•
This micrograph also demonstrates the highly
branched structure of the odontoblastic processes in
root dentin, which is thought to be responsible for the
granular layer of Tomes. The arrow and bracket
indicate the region of the hyaline layer.