Card Set Information

2010-10-03 14:33:08

root development and eruption
Show Answers:

  1. when does root development start?
    when the crown is complete and erupting
  2. what is the cervical loop made of?
    inner enamel epithelium and outer enamel epithelium squished together (no stellate rticulum or stratum intermedium)
  3. once the cervical loop extends deeper into the ectomesenchyme what does it become?
    hertwing's epithelial root sheath (HERS)
  4. how is dentin formed along the root?
    • HERS induces dental papilla to differentiate into odontoblasts
    • Odontoblasts leave the dentin matrix
    • HERS disintegrates
  5. what are epithelial rests of Malassez
    HERS that didn't disintegrate and get lost, they can become cystic and cause problems
  6. What can't enamel form in the root?
    without the stratum intermedium and stellate reticulum the ameloblasts cannot form
  7. what induces cells of the dental sac to become cementoblasts?
  8. what is the only slimy trail (matrix) to have a name?
    cementoblasts matrix-cementoid
  9. what are the cementoblasts cell bodies called and where do they leave it?
    • cementocytes
    • within the matrix
  10. through _____ the dental papilla now forms into the ___ of the tooth.
    • induction
    • pulp
  11. the ectomesenchyme from the dental sac ____ into the _____ ____ adjacent to the cementum
    • differentiates
    • periodontal ligament
  12. the ectomesenchyme from the___ ___ differentiates into the ____ ___ surrounding each tooth.
    • dental sac
    • alveolar bone
  13. what does the periodontal ligament anchor into?
    cementum and alveolar bone
  14. how are multirooted teeth formed?
    cervical loop splits into multiple roots
  15. what are the developmental disturbances during root formation?
    • enamel pearls
    • concrescence
    • dilaceration
    • accessory roots
  16. what is it when the ameloblasts get lost and start forming enamel in abnormal places?
    enamel pearls
  17. what is it called when two teeth get stuck together by cementum?
  18. what is it called when because of injury or pressure the HERS get distorted and make the roots bend?
  19. what is an accessory root?
    extra roots because of injury pressure or metabloic disease of HERS
  20. what kind of eruption is actual vertical movement of the tooth?
    active eruption
  21. what kind of eruption is it when gingiva recedes around tooth?
    passive eruption
  22. what is reduced enamel epithelium and what does it do?
    • enamel organ squished together
    • REE fuses with the oral epithelium and disintegrates it to make a tunnel for eruption
  23. what two kinds of cells are needed for primary tooth shedding?
    • osteoclasts
    • odontoclasts
  24. what cell dissolves the bone around the tooth in primary tooth shedding?
  25. what cell dissolves the roots of the tooth in primary tooth shedding?
  26. What happens when the primary tooth is not quite ready to come out?
    osteoblasts, odontoblasts and cementoblasts replace the reabsorbed bone and root. That is why kids teeth will feel really loose and then suddenly tighten up again
  27. what is the nasmyth's membrane?
    left over REE and oral epithelium that sticks to the newly erupted teeth and catches stain
  28. how do you remove the nasmyth's membrane?
    polishes off
  29. all succedaneous teeth form and erupt _____ to the primary teeth except the maxillary incisors that erupt _____ to the primary teeth.
    • Lingually
    • Facially
  30. what are the two types of developmental disturbances during eruption?
    • dentigerous cyst
    • eruption cyst
  31. what is a dentigerous cyst?
    the REE forms a cyst around the completely formed crown. it can displace teeth and cause pain and must be removed surgically
  32. what is an eruption cyst?
    a dentigerous cyst formed around the developing crown. when the tooth erupts it will go away
  33. What developmental disturbance during eruption is around a completely formed crown?
    dentigerous cyst
  34. what developmental disturbance during eruption is around a developing crown?
    eruption cyst
  35. true/false. a dentigerous cyst will go away on its own when it erupts?
    false, a dentigerous cyst must be removed surgically
  36. true/false. a eruption cyst must be removed surgically.
    false a eruption cyst will go away on its own when the tooth erupts