Gingivitis - experimental evidence

Question 1

is the supragingival environment aerobic or anaeriobic?

Answer 1

aerobic - oxygen levels vary

Question 2

is the subgingival environment aerobic or anaerobic?

Answer 2

anaerobic

Question 3

are the conditions supragingivally constant or variable?

Answer 3

variable -
moisture/osmotic pressure
temperature
shear forces

Question 4

are the conditions subgingivally constant or variable?

Answer 4

constant -
viscous
37*c
loosely packed community

Question 5

what gives the supragingival environment moisture and nutrients?

Answer 5

saliva

Question 6

what gives the subgingival environment moisture and nutrients?

Answer 6

gingival crevicular fluid

Question 7

bacteria in the supragingival environment feed off what?

Answer 7

dietary carbohydrates

Question 8

bacteria in the subgingival environment feed off what?

Answer 8

proteins derived from serum

Question 9

do gram +ve or -ve dominate supragingivally?

Answer 9

gram +ve

Question 10

do gram +ve or -ve dominate subgingivally?

Answer 10

gram -ve

Question 11

what kind of bacteria dominate supragingivally?

Answer 11

facultative anaerobes

Question 12

what kind of bacteria dominate subgingivally?

Answer 12

obligate anaerobes (GNABs)

Question 13

remember
The subgingival community will still be majority gram +ve but the key mediators of disease are gram -ve

Question 14

bacteria in subgingival plaque during disease diversifies.
what bacteria change?

Answer 14

prevotella % increases
porphyromonas % increases
fusobacterium % increases

Question 15

whats the name of the person who did lots of studies on the link between plaque and gingivitis and its treatments?

Answer 15

Harold Loe

Question 16

how did Harold Loe study the link between gingivitis and plaque?

Answer 16

dental students
ceased OH then restarted
monitored plaque levels and gum inflammation

Question 17

what did Harold Loe conclude from his study on the link between plaque and gingivitis?

Answer 17

ceasing OH lead to plaque formation and gingivitis

plaque formation changed - more filaments, anaerobes, spirochaetes

reversible - once OH restarted, plaque removed and gingivae returned to health

Question 18

Harold Loe did a study on chlorohexidine to find out what?

Answer 18

Is it the mechanical stimulation of the gums that is part of the process of restoring oral health

Question 19

how did Harold Loe study the effect of chlorhexidine?

Answer 19

dental students
ceased OH
Take chlorohexidine mouthwashes instead of brushing

Question 20

what did Harold Loe conclude from his study on chlorhexidine?

Answer 20

Didn’t need mechanical brushing, could use a antimicrobial agent.

Providing there wasn’t any gross plaque as can’t get penetration to deeper layers

Question 21

Harold Loe did studies on different age groups, what did he find from this?

Answer 21

have to consider underlying immunological status of the host

Children can cope with more plaque than older patients before getting gingivitis

Question 22

what did Harold Loe conclude from his study on toothbrushing frequency?

Answer 22

Need to clean every 12hrs before plaque builds up and cause tissue damage

Regular OH is effective

Even at 48hrs the plaque wasn’t at sufficient level to cause gingivitis

Question 23

why can’t you do studies on periodontitis?

Answer 23

as unethical to let trial subjects get irreversible damage

Question 24

why doesnt the specific plaque hypothesis apply to gingivitis?

Answer 24

no evidence removing one species prevents disease

Question 25

why does the non-specific plaque hypothesis apply to gingivitis?

Answer 25

gross build up of plaque is the risk factor

Target the build up of plaque to restore good oral hygiene

Question 26

why does the ecological plaque hypothesis apply to gingivitis?

Answer 26

depends on the amount and type of bacteria and conditions that cause disease