Chapter 8 Flashcards
what is periodontitis
- alveolar and supporting bone destruction
- can affect children and adults
- not based on age, but on clinical and radiographic findings
what causes perio
- bacteria, causing:
- inflammatory/immune events
- microscopic changes in the connective tissue and epithelium
- development of perio
what are the 4 stages of of histopathogenesis
- initial
- early
- established
- advanced
what is the advanced lesion
- alveolar and supporting
- loss of connective tissue attachment
- the inflammatory infiltrate spreads in the connective tissue
- plasma cells (B cells) predominant
what is a pocket
- a pathologically deepened gingival sulcus
- in disease, the junctional epithelium becomes pocket epithelium
when is it a periodontal pocket
- when inflammation spreads into the body of the connective tissue – decreases collagen
- gingival fibers and connective tissue are destroyed, followed by apical and lateral migration of the junctional epithelium
- remember, a pocket refers only to soft tissue, not to bone. this is referred to as attachment loss
- as a consequence to destruction of the gingival fibres and apical migration of the JE there is bone destruction
what will occur when the pocket depth increases in a periodontal pocket
- ideal for bacterial growth
- difficult to maintain
what are the 2 types of periodontal pockets
- suprabony
- infra bony
what cemental changes are seen in the root surface with disease
- surface is rough
- easily absorbs endotoxins
- and bacteria and their by-products
- called necrotic cementum
how is bone destroyed with perio
- PMNs release prostaglandins. PGE2 destroys bone and PGs activate osteoclasts
- endotoxins destroy bone, which are released by gram negative bacteria
- B-cells
- release of IL-1, which stimulates PMN and collagenase
- cytokines from macrophages destroy bone, IL-1 also stimulates PGE2
is the degree of bone loss correlated with the depth of pockets
- no
- radiographically, extensive bone loss can also be associated with shallow pockets, due to surgery or recession
what does the pattern of bone loss depend on
- the route of the inflammatory infiltrate and route of tissue destruction
what are the 2 patterns of bone loss
- horizontal
- vertical
what is horizontal bone loss
- gingiva -> bone -> PD (principle fibers)
- bone is lost equally
- related to suprabony pocket
- bone resorption occurs from the outer aspect
what is vertical bone loss
- inflammation travels directly from the gingiva into the periodontal ligament
- bone loss is more rapid on one side of the tooth than the other
- gingiva to PDL to bone
- base of the deepest portion of the bony defect is apical to the alveolar bone crest creating an infra bony defect
what are the different types of infrabony defects
- vertical bone loss
- classified according to the number of osseous (bony) walls REMAINING around the defect
what is a 3 wall defect with an infrabony defect
- 3 bony walls remain and one is missing (easiest to repair in surgery bc 3 walls to connect to)
what is a 2 wall defect with an infrabony defect
- 2 bony walls remain and 2 are missing
- ‘crater’-M and D on adjacent teeth are missing, buccal and lingual walls remain (most common)
what is a 1 wall defect with an infrabony defect
- one bony wall remains and 3 are missing
- ‘hemiseptum’ defect – only the buccal or lingual wall remains
how far does the bone destruction process radiate
- 2 mm of the plaque mass
what are some factors impacting the pattern of bone loss
- thickness and width of the interdental septum
- wider interdental septum (>2 mm) (posterior teeth) versus septal bone (anterior teeth)
- thus mandibular incisors - mostly horizontal loss
- greater than 2 mm – probably vertical
how do we classify periodontitis
- extent
- severity
- grade
what is the extent of periodontitis
- localized: less than 30% of sites involved
- generalized: more than 30% sites involved
what is the severity of periodontitis
- stage I: CAL 1-2 mm
- stage II: CAL 3-4 mm
- stage III/IV: CAL greater than or equal to 5 mm
