Role of Antibiotics in Periodontal Therapy

Question 1

What are six indications for systemic antibiotic therapy

Answer 1

aggressive periodontitis
failing implants
periodontal abscess (sometimes)
NUG (sometimes)
recurrent periodontitis
poor general response to initial therapy

Question 2

What is the rationale for using antibiotics

Answer 2

some periodontal pathogens (Aa, Pg, Pi) are invasive, making them difficult to eliminate by SRP

Question 3

What is the measurement of a pocket that it pretty hard to clean out

Answer 3

≥ 5mm

Question 4

Why is chronic periodontitis not routinely treatment with antibiotics (2 reasons)

Answer 4

root planing eliminates most subgingival bacteria associated with chronic periodontitis
host defense mechanisms are usually effective

Question 5

Systemic antibiotics are potentially helpful in periodontal therapy if what four things occur

Answer 5

they distribute to the pocket and its soft tissue wall
they reach inhibitory levels in the pocket
their levels are maintained for an adequate duration
they penetrate host cells and kill invasive bacteria

Question 6

Antibiotics are much more effective after this has been disrupted

Answer 6

biofilm

Question 7

What is a narrow spectrum antibiotic

Answer 7

effective against specific families of bacteria

Question 8

What is a broad spectrum antibiotic

Answer 8

acts against a wide range of clinically important bacteria

Question 9

This is bactericidal, but inactivated by beta lactamases

Answer 9

penicillins

Question 10

Where do penicillins reach effective levels

Answer 10

in the gingival fluid

Question 11

Penicillins don’t inhibit all of these strains

Answer 11

Aa

Question 12

Penicillins don’t penetrate what very well

Answer 12

epithelial cells

Question 13

This has enhanced tissue penetration and good activity against gram negatives

Answer 13

amoxicillin

Question 14

This is as effective as amoxicillin, and it is resistant to inactivation by beta lactamases

Answer 14

augmentin

Question 15

This has bactericidal activity against strict anaerobes but has less potent activity against facultative bugs like Aa

Answer 15

metronidazole

Question 16

This is bacteriostatic against most periodontal pathogens

Answer 16

tetracyclines

Question 17

In which fluid does tetracyclines, doxycycline, and fluoroquinolones reach higher levels

Answer 17

gingival fluid compared to blood serum

Question 18

tetracyclines inhibit this

Answer 18

collagenases; which mediates collagen breakdown in periodontitis

Question 19

tetracyclines are actively accumulated by which cells

Answer 19

oral epithelial cells
gingival fibroblasts
PMNs

Question 20

This is bactericidal and extremely active against Aa but less active against anaerobic bacteria like Pg

Answer 20

fluoroquinolones

Question 21

What is the mechanism of fluoroquinolones

Answer 21

penetrate epithelial cells and phagocytes and can kill invasive bacteria

Question 22

This appeared to enhance PMN bactericidal ability again Aa and is the most significant when the bacteria:PNM ratio is high

Answer 22

ciprofloxin

Question 23

This has potent bacteriostatic activity against strict anaerobes and is less effective against facultative pathogens like Aa

Answer 23

clindamycin

Question 24

These are not especially effective at concentrations seen in gingival fluid and has weak activity against Aa

Answer 24

macrolides (erythromycin)

Question 25

These can reach high concentrations in tissue, and has good activity against Aa, P gingivitis, and other gram (-) anaerobes

Answer 25

azithromycin | clarithromycin

Question 26

What is the mechanism of azithromycin and clarithromycin

Answer 26

penetrates epithelial cells and kills invasive bacteria; also taken up by PMNs and fibroblasts

Question 27

Macrolides (-mycin's) produce what kind of effects

Answer 27

anti-inflammatory

Question 28

Azithryomycin induces a decrease in what

Answer 28

GCF IL-8 and TNF content in healthy subjects

Question 29

True or False | systemic clairthromycin reaches high levels in inflamed gingiva than in healthy gingiva

Answer 29

True

Question 30

True or False | Azithromycin does not help eliminate invasive Aa infection from cultured oral epithelium cells

Answer 30

False, it does

Question 31

In the presence of an overwhelming Aa infection these kill Aa more effectively

Answer 31

PMNs loaded with clarithromycin or azithromycin

Question 32

True or False | Antibiotics like cyclines, floxacin, and mycin's can kill invasive bacteria

Answer 32

True

Question 33

What would an ideal concentration vs MIC in order for the antibiotics that treat periodontitis to be effective

Answer 33

10x concentration vs MIC

Question 34

What are three methods to determine which antibiotic to use

Answer 34

empirical approach, based on RCT data identify pathogens at the site with a molecular technique then prescribe an antibiotic that will inhibit them culture isolated bacteria to identify and then determine the susceptibility to antibiotics

Question 35

This permits detection of specific pathogens in subgingival plaque or saliva specimens; available as a reference lab service but not many available

Answer 35

molecular tests for microbial identification

Question 36

What are some advantages of molecular tests

Answer 36

``` plaque/saliva easy to collect non-invasive test specific for bacteria more sensitive tests require DNA not live bacteria ```

Question 37

What are some advantages of bacterial culturing

Answer 37

reflects the viable bacteria in the pocket can assess the predominance of a particular pathogen can grow and study unusual bacteria can determine antibiotic susceptibility

Question 38

What are some disadvantages of bacterial culturing

Answer 38

``` few labs available time consuming and costly problems with transport difficult to grow more organisms accuracy depends on good sampling not very sensitive ```

Question 39

What should be completed before microbiological testing

Answer 39

initial periodontal therapy, then assess the response, then prescribe if needed

Question 40

What are the typical antibiotic regimens for aggressive and recurrent periodontitis

Answer 40

amoxicillin and metronidazole | azithromycin for penicillin allergies

Question 41

systemic antibiotics are not consistently beneficial unless what

Answer 41

the biofilm is disrupted by SRP

Question 42

antibiotics enhance treatment of which type of periodontist more

Answer 42

aggressive

Question 43

Which should come first, antibiotics or SRP

Answer 43

SRP

Question 44

What are three adverse side effects associated with systemic antibiotics

Answer 44

induction of antibiotic resistance induction of microbial overgrowth hypersensitivity/toxicity

Question 45

This type of antibiotic delivery avoids most adverse side effects

Answer 45

local antibiotic delivery

Question 46

What are some advantages of local delivery of antibiotics

Answer 46

high drug concentration sustained therapeutic levels effective drug levels can be attained at sites that are difficult to reach adverse side effects are minimized

Question 47

What are some short comings of local delivery of antibiotics

Answer 47

less effective than systemic antibiotics at eradicating invasive bacteria can't eliminate pathogens from the entire oral cavity local delivery technique can be time consuming and not cost effective

Question 48

What is the current application for controlled release local antibiotic delivery

Answer 48

treatment of localized recurrent periodontitis in cases that are otherwise stable