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 4mm+

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) (also known as gingival pocket)

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 these fibers, 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

disease sites

area of tissue destruction, just bc a pocket is present does not mean the patient has an active disease

inactive- stable

active- continued apical migration of the junctional epithelium over time

periodontal pocket

apical migration of the JE

destruction of periodontal ligament fibers

destruction of the alveolar bone

suprabony pocket

base of the pocket is coronal to the crest of the alveolar bone

horizontal bone loss

infrabony pocket

base of the pocket is apical to the crest of the bone

vertical or angular bone loss

infrabony defects

classified by the number of bony walls surrounding the tooth

three-wall: three bony walls remain and one is missing

two-wall: two bony walls remain and two are missing, interdental crater most common

one-wall: one bony wall remains and three are missing, hemiseptum (only the buccal or lingual wall remains)

osseous crater

when bone loss occurs in the interdental alveolar bone, the contour of the bone from facial to lingual dips apically

affects two adjacent root surfaces to a similar extent

furcation involvement

on a multi-rooted tooth when periodontal infection invades the area between and around the roots, resulting in a loss of alveolar bone between the roots of a multirooted tooth

continuous disease model of disease progression

(prior to 1980)

periodontal disease worsened throughout the entire mouth in a slow and constant rate; all cases of untreated gingivitis led to periodontitis

intermittent disease progression theory

current research- periodontal disease is characterized by periods of disease activity and inactivity; destruction does not occur in all parts of the mouth at the same time (susceptibility to periodontitis varies)

incidence

the number of new disease cases in a population that occur over a given period

prevalence

number of all cases (both old and new) of a disease that can be identified within a specified population at a given point in time

variables associated with the prevalence of periodontal disease

gender, race, socioeconomic status, age, behavior (like tobacco use), access to dental care

examples of commonly used periodontal indices

CPITN- community and periodontal index of treatment needs

EIBI- Eastman interdental bleeding index

GBI- gingival bleeding index

GI- gingival index

PSR- periodontal screening and recording