exam 2 (L7) - osseous defects Flashcards
what are some causes (etiology) of alveolar bone loss?
- extension of gingival inflammation
- trauma from occlusion (secondary etiological factor)
- systemic disorders
- genetics
- host response
how might gingival inflammation extend to cause alveolar bone loss?
- extends along collagen fibers, follows course of blood vessels, and enters alveolar bone
- pathways differ in interdental bone (septum) and facial bone
- max enter maxillary sinus and cause thickening of the sinus membrane
what 2 pathways were mentioned for gingival inflammation to reach alveolar bone?
- may immediately enter bony area from pocket, then exit back into the tissue (interdental)
- may course through the PDL before entering the trabecular bone (facial)
- type influences whether horizontal or angular BL
what is the discussed pathobiology (cause) of an osseous defect?
- bone resorption factors close to bone
- bacterial plaque in radius of 1.5 - 2.5 mm to bone
- angular defects if interdental septum is >2.5 mm wide
thin bone (2.5 mm) result in what types of bone loss, respectively?
- thin bone = horizontal resorption
- thick bone = angular resorption
what possible situations affect the equilibrium seen in loss of alveolar bone (BL)?
- increased resorption during normal bone formation
- decreased formation during normal resorption
- increased resorption + decreased formation
where does bone formation always occur during periodontal disease?
in areas of resorption, during periods of remission
what model is representative of bone formation/resorption in periodontal disease?
- random multiple burst model of disease progression:
+ disease is episodic
+ periods of exacerbation and remission - bone loss in perio happens when destruction > formation
when/why does buttressing bone form?
- forms in an attempt to support weak/bony trabeculae
- when it forms, it grows away from pathogenic resorption area, and can cause ledges/horizontal defects
what types of buttressing bone were discussed?
- central = occurs within jaw
- peripheral = occurs on external surface of jaw
+ creates ledge deformity that acts as severe plaque trap
what are some common osseous defects?
- horizontal bone loss (suprabony pockets)
- angular BL (vertical/infrabony pockets)
- ledges
- reverse architecture
- furcation involvement
what is reverse architecture?
- compensation mechanism for horizontal BL
- involves loss of interdental bone w/out the loss of interradicular bone
what types of surgery work best for 1, 2, and 3-wall defects?
- 3- wall = regenerative surgery (most stable)
- 2-wall = still GTR, but less stable than 3-wall
- 1-wall = so severe that it may be better to remove tooth than do osseous surgery due to poor prognosis
which furcation has the best surgical outcome?
F2
which furcation has resective surgery to open the flap so pt. can maintain good hygiene in the furcation?
F3
