1. Derived from ectomesenchyme -Mesoderm, and makes up the bulk of the tooth, and protects the pulp
  2. Mature dentin is only_______________calcified with______________________-
    • 70%
    • calcium hydroxyapatite
  3. Feels rougher than enamel, but it is softer than enamel and can be removed with instrumentation
  4. true or false. Dentin is avascular so it gets its nutrition from the pulp
  5. During what stage do the outer cells of the dental papilla form odontoblasts? The odontoblasts lay down predentin and leave one long cytoplasmic extension in the dentin?
    Apposition of dentin
  6. During the apposition of dentin, the outer cells of the dental papilla form__________________
  7. Odontoblasts lay down what?
  8. true or false. Apposition can keep going because you keep your odontoblasts
  9. What are the two steps in the maturation of dentin?
    • primary mineralization
    • secondary mineralization
  10. globules calcify and expand and fuse together to create globular dentin
    primary mineralization phase during maturation of dentin
  11. as globules calcify, they expand, but do not fuse completely, which creates interglubular dentin that is less mineralized
    secondary mineralization phase during maturation of dentin
  12. Name 4 components of mature dentin
    • dentinal tubules
    • odontoblastic process
    • dentinal fluid
    • afferent axon
  13. extend from the DEJ to the outer wall of the pulp (the cave)
    dentinal tubules
  14. the tail end of our odontoblasts (the cell within the cave)
    odontoblastic process
  15. the tissue fluid surrounding the cell membrane of the odontoblast (where heat and cold affect the tooth)
    dentinal fluid
  16. the nerve that receives sensation for the tooth, the nerve cell body is located in the pulp of the tooth (axon runs in the tube, the cell body is in the pulp)
    afferent axon
  17. true or false. The direction of the tubule reflects the pathway the odontoblast took
  18. overall tubule course which resembles a large S
    primary curvature of dentinal tubule
  19. small delicate curvature in dentinal tubules showing the daily changes in odontoblasts during apposition
    secondary curvature
  20. types of dentin are divided into what 2 categories?
    • location
    • time of formation
  21. name the 4 types of dentin by location.
    • peritubular dentin
    • intertubular dentin
    • mantle dentin
    • circumpulpal dentin
  22. dentin that creates the dentinal tubule (wall of cave)
    peritubular dentin
  23. dentin found between between each of the tubules
    intertubular dentin
  24. first dentin to form, closest to the DEJ (outside layer)
    mantle dentin
  25. dentin that surrounds the pulp
    circumpulpal dentin
  26. Name the 4 types of dentin by time of formation.
    • primary dentin
    • secondary dentin
    • tertiary dentin
    • sclerotic dentin
  27. dentin formed before the completion of the apical foramen, normal alignment of tubules and more calcified than secondary
    primary dentin
  28. dentin formed after the completion of the apical foramen, less calcified than primary dentin, formed to protect the pulp
    secondary dentin
  29. formed in response to trauma, irregular alignment of tubules because it is laid quickly, formed to protect the outer layer of dentin
    tertiary dentin
  30. because of trauma or age, the odontoblastic process die and leave the tubule, the tubule is then filled with more dentin
    sclerotic dentin
  31. name 2 microscopic features of mature dentin
    • imbrication lines of von ebner
    • contour lines of owen
  32. lines in mature dentin that are just like the lines of retzius
    imbrication lines of von ebner
  33. darkened areas in dentin that show some sort of disturbance in the apposition
    contour lines of owen
  34. what is the most pronounced contour line of owen?
    neonatal line
  35. true or false. diameter or the tubules in dentin starts to narrow with age, and as more dentin is laid and seals off the communication between the dentin and the pulp.
  36. name 2 clinical considerations of dentin
    • caries chute
    • hypersensitivity
  37. dentin is__________________and more prone to caries
    less calcified
  38. What do bacteria use dentinal tubules as to get to the pulp?
    chutes to the pulp
  39. Why when a cavity reaches the dentin, must it be repaired as soon as possible?
    because bacteria may use the dentinal tubules as a chute to get the pulp, and they spread fast once they reach the dentin
  40. Afferent axons are where in the tooth?
    in the dentinal tubule
  41. Afferent axon nerves in the dentinal tubules translate all stimuli (hot, cold, pressure, dehydration) as_______________.
  42. true or false. The exact mechanism for this hypersensitivity in the dentin is unknown
  43. What are 3 ways to occlude the dentinal tubules that can help diminish hypersensitivity?
    • fluoride
    • laser treatment
    • composite fillings
  44. formed from the central cells of the dental papilla, which came from the ectomesenchyme- mesoderm
  45. what part of the tooth is functional by association?
    pulp (it makes everything else work)
  46. Why is the pulp involved with the formation of dentin?
    because the odontoblasts live in the outer layer of the pulp
  47. Why does the pulp have a sensory function?
    because the nerve cell bodies are located in the outer layer of the pulp
  48. Pulp has a nutritional function for the tooth through the__________________
  49. Why does pulp have a protective function?
    because the secondary dentin is formed from the odontoblasts in the outer layer of the pulp
  50. Name 6 anatomical features of the pulp
    • pulp chamber
    • coronal pulp
    • pulp horns
    • radicular pulp
    • apical foramen
    • accessory canals
  51. the mass of pulp in the middle, follows the shape of the tooth
    pulp chamber
  52. the pulp in the crown area
    coronal pulp
  53. smaller extensions of pulp into the crown
    pulp horns
  54. the pulp in the root areas, it has openings through the dentin and cementum, out to the surrounding periodontal ligament
    radicular pulp
  55. the opening of the pulp into the periodontal ligament - usually at the very apex of the tooth
    apical foramen
  56. What structure allows arteries, veins, lymphatics and nerves to enter the tooth
    apical foramen
  57. extra opening from the pulp to the periodontal ligament that usually runs perpendicular to the root of the tooth
    accessory canals
  58. Accessory canals form because__________________________________ran into a blood vessel while it was forming, so it just formed a little canal around the vessel
    Hertwig's epithelial root sheath (HERS)
  59. Name 6 microscopic features of pulp
    • fibroblasts
    • odontoblasts
    • white blood cells
    • collagen fibers
    • extensive vascular supply
    • pulp stones
  60. true or false. pulp is a connective tissue, so it is mainly full of fibroblasts
  61. may be present in the pulp sometimes, they are calcified masses of dentin inside the pulp chambers, they only really cause problems when trying to do endodontic therapy
    pulp stones
  62. inflammation of the pulp
  63. Name 3 things that might cause pulpitis
    • extensive caries
    • cavity preparation
    • traumatic injury
  64. true or false. The pressure from the inflammation of pulpitis can cause severe pain
  65. name 2 ways the the pressure from pulpitis might be relieved?
    • incision and drainage
    • fistula
  66. a channel that forms in the bone or soft tissue to drain infection from pulpitis
  67. the inflammation from pulpitis can exit the pulp through the apical foramen and cause a/an____________________
  68. What must be done to save a tooth from pulpitis?
    root canal therapy
  69. why is it important to crown a tooth once a root canal has been performed on it?
    without the pulp, the tooth becomes brittle and more prone to breakage
  70. a material that comes from a tree that is used to fill the empty canal once the pulp has been removed from a root canal, the body does not react to it
    gutta percha
Card Set
Dentin and pulp 1