chapter 3: overview of diseases of the periodontium

characteristics of healthy periodontium

clinical: pink, firm interdental papillae, no bleeding, 1-3 mm probing depth

histological: JE coronal to the CEJ, supragingival fibers intact, alveolar bone intact, periodontal ligament intact

characteristics of gingivitis

some reversible tissue damage

clinical: red, swollen (edematous), bleeding likely, sulcus depth 3mm+

histological: JE at CEJ, supra-gingival fiber destruction, alveolar bone intact, periodontal ligament intact

characteristics of periodontitis

permanent destruction

clinical: pink or purplish, swollen (edematous) or fibrotic, bleeding or pus, probing depths mm+

histological: JE on cementum (APICAL MIGRATION), supragingival fibers destruction (makes it easier for JE to migrate), alveolar bone destruction, periodontal ligament destruction

gingivitis is observed clinically ____ days after plaque biofilm accumulates in the gingival sulcus

4-14

gingival tissue enlargement

caused by acute and chronic gingivitis

excess collagen fibers (body’s attempt to repair the tissue damage) → deeper probing depths/pseudopocket (JE remains in its normal position)

cyanotic gingiva

reddish-blue color of gingivitis

blood flow increases → blood vessels become congested → slows flow of oxygenated blood to tissues and the flow of unoxygenated blood away from the tissues → unoxygenated blood pools in the gingival tissues

fibrotic tissue

common in periodontitis

firm, light pink with a leathery consistency

transseptal fiber bundles

resilient bands of gingival ligament fibers that run from one tooth to another across the crest of the bone (can usually withstand periodontal inflammation)

if inflamm is severe enough to overcome this, tooth displacement/pathologic tooth migration occurs

in health and gingivitis, the crest of the alveolar bone is located approximately ____ to the CEJ

2-3 mm apical

horizontal bone loss

alveolar bone is reduced in height, but the crest margin remains perpendicular to the long axis of the tooth

vertical bone loss

uneven reduction in the height of alveolar bone. resorption is more rapid next to the root → trench-like areas

pathway of inflammation into alveolar bone

horizontal bone loss (path of least resistance): gingival connective tissue → alveolar bone → PDL

vertical bone loss: gingival connective tissue → PDL (too weak to act as a barrier) → alveolar bone

infrabony defect

osseous defect- involves the loss of bone

two types:

• intrabony defects- bone resorption is uneven and oblique, primarily affects one tooth (one-wall/hemiseptal, two-wall, three-wall)

• osseous crater- the contour of the bone from facial to lingual dips apically, affects two adjacent root surfaces