Periodontitis

Question 1

periodontal disease

Answer 1

a group of distinct clinical entities that affect the periodontium, including the gingiva, gingival attachment, periodontal ligament, cementum and alveolar bone
microbial origin

Question 2

periodontal disease includes

Answer 2

gingivitis and periodontitis

Question 3

different surfaces for biofilm to form

Answer 3

hard surface - tooth
soft tissue - epithelium

Question 4

gingival crevice

Answer 4

exposed to the outside environment
low oxygen penetration
close apposition to immune cells
bathed in GCF - high protein
different surfaces for biofilm to form

Question 5

progression from gingivitis to periodontitis

Answer 5

can take many years for chronic marginal gingivitis to progress to periodontitis
influenced by microbial population dynamics
introduction of a new population
stochastic changes
change in immune status

Question 6

periodontal pocket

Answer 6

a distinct environment
anaerobic, with slightly alkaline pH
generally Gram + next to tooth and Gram - interacting with the epithelium

Question 7

change in any factor can influence the others such as

Answer 7

more plaque - more biofilm progression
failure of immune response
localized injury/inflammation increasing GCF flow
keystone organisms

Question 8

acquired periodontists

Answer 8

manifestation of systemic disease
neutropenia, leukaemia
genetic disorders - neutropenia
metabolic disorders - diabetes mellitus

Question 9

changing composition of subgingival microbiome

Answer 9

progressive increase in anaerobic environment
lower redox potential (less oxygen) in the gingival crevice
increase in GCF flow, slightly alkaline pH
gram-negative rods are the dominant species in periodontitis

Question 10

changing composition of subgingival microbiome

Answer 10

there are some specific organisms that are dominant in gingivitis and periodontitis that are not readily detectable in healthy biofilms

Question 11

pathogen

Answer 11

an organism that can produce disease

Question 12

primary pathogen

Answer 12

establish themselves in a niche normally occupied by commensal microbial populations
able to cross anatomic barriers or overcome other host defenses that limit commensals

Question 13

opportunistic infections

Answer 13

infection when normal host defenses are diminished
can be caused by primary pathogen or normal commensal bacteria

Question 14

periodontal pathogens are all

Answer 14

all are Gram-negative anaerobic bacteria

Question 15

evidence for role in periodontal disease

Answer 15

the organisms are present in diseased sites and their numbers increase with disease
the organisms possess the ability to cause damage to periodontal tissue
e.g. enzymes that breakdown gingival tissue, and components that induce pro-inflammatory cytokines production
animal studies showed alveolar bone loss

Question 16

virulence genes

Answer 16

help pathogens survive and proliferate
adherence/colonization factors
exotoxins
enzymes
immune evasion
biofilm formation or survival genes

Question 17

adherence/colonization factors

Answer 17

bind to host cells
fimbriae, afimbrial adhesins, capsule

Question 18

exotoxins

Answer 18

secreted proteins to effect host function
wide variety of functions
can generally be inactivated by hearing

Question 19

enzymes

Answer 19

degrade host structures
e.g. proteases: degrades connective tissue
e.g. lipases: lyse host cell membranes

Question 20

immune evasion

Answer 20

hide from the immune system
protective structurers (capsules, antigenic variation)
suppress immune responses
physically hide from the immune system (bladder, or inside a cell)