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
which teeth are best for class II furcation involvement with therapy?
mandibular 1st molars
are class III furcations good for GTR?
no
in horizontal BL, what are the goals of treatment?
- pocket reduction
- correct reverse architecture
in horizontal BL, what are some potential tx options?
- SRP
- GV
- OFD
- OS
what are tx goals with angular BL?
- pocket reduction
- restoration of attachment apparatus
what tx options are available for angular BL?
- OS
- GTR
what is the goal of tx with furcation defects?
- eliminate furcation defect
- provide self-cleaning area for pt
what tx options are available for furcation defects?
- SRP
- OFD
- OS
- GTR
what type of flap should be used for osseous surgery?
- full thickness flap, positioned apically
- need full-thickness flap any time you touch bone
what type of flap should be used for GTR?
- full thickness flap, coronally positioned
- full-thickness flap aids in wound healing
- sulcular incisions help preserve soft tissue
- vertical incisions allow apical positioning/access of flaps
what incision types are used for osseous surgery?
- normally scalloped incisions, but sulcular if there is minimal keritinized tissue to avoid mucogingival defects
- additional vertical incisions needed to place apically (may cause scarring in esthetic zone)
what determines how much soft tissue to remove?
the amount of keratinized tissue available (helps avoid MG defects)
what incision type is used for GTR?
- sulcular incisions
- may need additional vertical incisions for coronal positioning of flap
