Locally delivered antimicrobials Flashcards
(45 cards)
What evidence suggests that periodontitis has a bacterial cause?
- People an develop acute periodontal infections following periodontitis
- We know the relationship between plaque levels, gingivitis and periodontitis
- Theres an efficacy of antibiotics in treating periodontitis
- Host immunological responses to periodontitis s
- Plaque bacteria has pathogenic potentila
- Theres studies present using snail models showing periodontitis has a bacterial cause
- Immunisation studies in animals also shows evidence for periodontitis having a. bacterial cause
What is the main treatment we use to treat periodontal disease?
Mechanical therapy like scaling
What are the limits to mechanical therapy?
Poorer treatment options for sites with furcation involvement compared to molar flat surfaces
When might mechanical therapy fail to remove periodontal pathogens?
- Sub epithelial gingival tissues are out of reach so can’t remove bacteria from them
- If plaque is located in the connective tissue its hard to reach
- Crevicular epithelial cells are hard to remove
- The cementum and dentinal tubules are altered
- Sub gingival calculus is hard to remove
- Some anatomical features make it harder to remove bacteria
- Colonies on the dorsal of the tongue. tonsils an oral mucosa aren’t affected by scaling
Give examples of some antimicrobials we use in dentistry
- 0.2% chlorhexidine gluconate
What does research show about the use of 0.2% chlorhexidine gluconate?
In the mouth studies have shown that chlorhexidine gluconate has no effect
Why does 0.2% chlorhexidine gluconate have no effect in the mouth?
Due to gingival crevicular fluid
Why is gingival crevicular fluid the reason 0.2% doesn’t work?
Theres a low volume but a high flow rate
GCF is cleared out 40 times an hour so if anything is added it is rapidly cleared
Give examples of devices that have been used to try and delivery antibiotics?
- EVA fibre containing 25% tetracycline HCl
- Chlorhexidine (2.5mg) in hydrolysed gelatine
- Minocyline 2% lipid gel
- Metronidazole 25% in a mono/triglyceride gel
- Doxycycline hyclate (8.8%) resorbable gel
- Minocycline HCl (1 mg) encapsulated microspheres
Which of the devices used to try and deliver antibiotics is not Resorbable?
EVA fibre containing 25% tetracycline HCl
How do we evaluate the effectiveness of varying devices used to deliver antibiotics?
- Read studies critically and be clear about what is being measured
- We check Pocket probing depth
- We check Gingival recession
- We check Clinical attachment level
- We check Bleeding on probing
What is a reliable indicator of periodontal stability?
The absence of bleeding on probing
What product is used to administer 25% tetracycline in an ethylene vinyl acetate fibre?
Actisite
What is Actisite?
It is a thin fibre that contains tetracycline that reduces the number of bacterial which infect gums
Where is Actisite placed?
It is places into the infected pocket between the gum and tooth
When is Actisite removed?
Usually after 10 Days
Is tetracycline usually bacteriostatic or bactericidal?
Bacteriostatic
When used in Actisite is tetracycline bacteriostatic or bactericidal?
bactericidal
6 months after treatment what results does Actisite show?
- Pocket depth decreases
2. percentage of sites with no bleeding on probing increases from 50% fo 63%
What product is used to administer 2.5 mg chlorhexidine gluconate in a biodegradable gelatine chip?
Periochip
What do you have to weary of when giving patients a periochip
Must tell your patient that perio chips contain gelatine as some patients may not be comfortable with this
How do periochips work?
They release chlorhexidine via diffusion
A chip is put into the patients mouth and this gel breaks down to release chlorhexidine
What is the benefit of periochips over Actisite ?
You don’t have to remove periochips as the work by breaking down
After 3 month what changes are seen in the mouth following placement of a periochip?
pocket depth decreases by -1.36
