Perio Lecture 2

  1. Supporting structures of the periodontium (4)
    • Gingiva
    • PDL
    • Cementum
    • Alveolar Bone 

    *function as a single unit
  2. Part of the tooth that includes the PDL cementum and alveolar bone
    attachment apparatus
  3. connective tissue that connects the tooth root to the bone via the cementum
  4. True/False: all of the fibers are not perpendicular to the tooth; different fibers take different stresses.
  5. what is the PDL made of?
    Collagen fibers
  6. the tensile strength of the PDL is great than
  7. what is the average width of the PDL?
    0.2 mm (related to function)

    0.2 mm is a static measurement – if you increase that measurement, there will be an adaptation of the bone to bring that measurement back to 0.2 mm. Also explains why a widened PDL has a force on the tooth.
  8. Functions of the PDL (3)
    • allows movement of the tooth in socket
    • acts as a "shock absorber" during infection
    • provides sensory information during function
  9. What happens to the PDL with loss of alveolar bone?
    it disappears and this increases mobility of the tooth
  10. little fibers at the end of the PDL that inject into the cementum and the alveolar bone to help keep the PDL connected
    Sharpey's fibers
  11. What are the 6 principle fibers of the PDL?
    • Transseptal
    • aveolar crest 
    • horizontal
    • oblique
    • apical
    • interradicular (only for multi rooted teeth--located in the furcation)
  12. transeptal fibers run inter proximally ____ the bony crest
  13. When healthy the alveolar bone is ___ mm apical to the CEJ
  14. how to alveolar crest group fibers run?
    downward from the heigh of cementum to alveolar crest
  15. Horizontal fibers form ____ ___ to the long axis of the tooth
    right angles
  16. fibers that run upward form cementum to alveolar bone-->tension fibers
    oblique fibers
  17. which fibers prevent the teeth from being drive in the apical direction and constitute the majority of the PDL
    oblique fibers
  18. 5 physical functions of the PDL
    • attach teeth to bone
    • secure gingival tissues in proper relationship to teeth 
    • shock absorption during occlusal load
    • transmission of occlusal forces of the bone
    • provides "casing" of protection for nerves and vessels of the dental unit
  19. 3 formative and remodeling functions of the cells of the PDL
    • formation and resorption of bone, cementum and the PDL itself
    • accommodation to occlusal forces
    • repair of injuries
  20. True/False: If the PDL tears with too large of a force, chances that the PDL may not reform and ankylosis will occur. Root resportion may result and tooth may need to be extracted.
  21. True/False: When the tooth is moved toward the one side the opposite side side will expand out to enlarge the PDL space and the other side will get smaller to keep the 0.2 mm width
  22. What is the nutritional function of the PDL
    provides nutrients to cementum, bone and gingiva via blood vessels
  23. what is the sensory function of the PDL
    provides tactile, pressure, and pain sensation vita trigeminal nerve
  24. elimination function of the PDL
    provides lympathic draining
  25. calcified avascular tissue that forms the outer covering of the anatomic root
  26. Fill in the following regarding cementum

    primary purpose:
    CEJ morphology:
    • primary purpose: anchor teeth via PDL
    • type: cellular and acellular
    • CEJ: varied
  27. True/False: cementum deposition is continuous
  28. Cementum repair is dependent on viable _____
    connective tissue
  29. True/False: repair can occur in devitalized teeth
  30. Type of cementum that is first to be formed, in the cervical 1/2 to 1/3 of the root surface and shows significant calicfication
    acellular cementum
  31. type of cementum that is formed after full eruption to occlusal plane, less calcification and thicker layer than acellular cementum
    cellular cementum
  32. the type of CEJ that occurs 5-10% of the time
    space between the cementum and enamel
  33. the type of CEJ that occurs 30% of the time
    end to end relationship between enamel and cementum (they meet but don't overlap)
  34. the type of CEJ morphology that occurs 60-66% of the time
    cementum overlapping enamel 

    C over E!
  35. usually found in the apical 1/3 of the root, super eruption of the teeth, low-grade periapical irritation and associated with Paget's disease is characteristic of what?
    Generalized Hypercementosis
  36. usually related to excessive force of ortho and or occlusion
    spikelike hypercementosis
  37. what are the 6 local etiologies for cementum resorption
    • occlusal trauma
    • orthodontic movement
    • erupting or misaligned teeth
    • cysts/tumors
    • replanted and or transplanted teeth
    • periapical and or periodontal disease
  38. what are the four systemic etiologies for cementum resorption
    • calcium deficiency
    • hypothyroidism
    • paget's disease
    • hereditary fibrous osteodystrophy
  39. True/False: 

    1. cementum repair requires presence of viable connective tissue
    2. epithelium will NOT block repair process
    3. Cementum repair possible in vital and devitalized teeth
    • 1. True
    • 2. false--it WILL block repair process
    • 3. true
  40. The following are characteristics of: 

    Dysregulated bone remodeling
    Excessive bone breakdown and subsequent disorganized new bone formation
    Multiple bones - pelvis, femur, and lumbar vertebrae, and skull
    Male:female (3:2)
    > 55 yrs old
    Genetic, virus?
    Bisphosphonate, calcitonin
    Paget's disease
  41. fusion of the cementum and alveolar bone without the presence of a PDL
  42. Sounding of an ankylosed tooth by percussion differs from that of a tooth with a PDL. Similar to percussion of implant--- why?
    without the PDL acting a shock absorber, the sound is being transmitted through the bone.
  43. Ankylosis is seen in teeth with (3)
    cemental resorption

    chronic peri-apical inflammation

    tooth replantation
  44. portion of the maxilla and the mandible that forms and supports the tooth sockets (alveoli)
    alveolar process
  45. True/False: the alveolar process remains intact after tooth loss

    gradual resorption after tooth loss
  46. When does the alveolar process form?
    it forms with the erupting tooth and PDL
  47. ____ _____ forms the skeletal structure at the apical portion of the alveolus.
    basilar bone
  48. What two things can happen if the root proximity is too small (narrow)
    • little blood supply 
    • faster bone loss
  49. True/False: Osseous crest should not be at the CEJ in healthy people because need cementum coronal to the osseous crest to allow for a soft tissue attachment.
  50. The osseous crest parallels ___
    CEJ-CEJ between teeth
  51. the denuded areas extending through the marginal bone

    looks like the tooth is completely coming out (the entire length of the root is coming out)
  52. isolated areas in which the root is denuded in bone

    Looks like just a portion of the root or apex is showing
Card Set
Perio Lecture 2
Perio Exam 1 Material