1. Dentin
pattern of mineralization
Root dentin formation
Physiologic 1ry ,2ry and 3ry dentin
Ahmed Emam

3. Dentinogenesis
acellular zone separates
ameloblasts from dental
papilla

4. Dentinogenesis - Secretory Stage

5. Odontoblasts and process
Dentin
Odontoblast process
Pulp
Odontoblast cells

6. Note: collagen fibers & odontoblastic processes in tubules

7. Dentinogenesis
First sign of dentin
formation.

8. `
arrows show von
Korff’s fibers

9. Odontoblasts produce
organic matrix &
crystals.
Note: mineralization
foci forming mantle
dentin

10. MANTLE DENTIN
CIRCUMPULPAL
DENTIN
Maturation of dentin

11. Begin of Crystallization
Matrix vesicle
Crystal lodgment
Rupture of the MV and
begin of mineralization
Maturation of dentin

15. Types of dentin:
globular/interglobular

16. Inter-globular dentin

17. Interglobuler
dentin

18. Interglobular Dentin
Dentino
Enamel
Junction
Dentinal
Tubules
Interglobuler
dentin

19. Odontoblast
processes

20. Hard Tissue Formation
Bell Stage

22. Formation of
Hertwig’s epithelial
root sheath.

25. Sheath grows around
dental papilla/future pulp.

26. The Completed Root
Incremental
layering of
cementum.
Alveolar bone
Pulp

30. Dentin
Cementum
Granular layer
of Tom
Hyaline layer

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.

32. DENTIN CLASSIFICATION
Types of dentin:

38. Primary
physiological
dentin
Secondary
physiological
dentin

39. Secondary
physiological
dentin
Tertiary
dentin
Primary
physiological
dentin

40. Dead tracts
Tertiary
dentin
Secondary
physiological
dentin
Primary
physiological
dentin

41. THE END
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you