Locally delivered antimicrobials- can they be used to treat periodontitis?

Question 1

evidence for the bacterial aetiology for periodontitis?

Answer 1

1. can be treated with antibiotics
2. plaque levels are related to gingivitis/ periodontitis
3. systemic antibiotics can treat periodontitis
4. host immune response shows elevated serum ig to perio pathogens
5. animal models prove bacterial aetiology

Question 2

what are 2 limitations of mechanical therapy?

Answer 2

1. poor treatment outcomes for sites with FURCATION involvement/ harder to clean sites. e.g. in 600 pt study, the majority of teeth lost were molars with *
2. fails to remove some periodontal pathogens that are 1) in sub-epithelial gingival tissue like a. actinomyces 2) in the GCF like p. gingivalis

Question 3

0.2% chlorohexidine gluoconate is gold standard antimicrobial. but, when we use it to WASH out the pocket AFTER scaling, it makes NO difference…why?

Answer 3

GCF in pockets has low volume but a HIGH FLOW RATE…0.5um GCF is renewed 40x every HOUR!
There is rapid clearance in pockets therefore chlorohexidine gets washed out.

this is why we need to locally deliver antimicrobials like chlorohexidine using using DEVICES to keep them in place

Question 4

evidence that our locally delivered antimicrobial device has worked?

Answer 4

absence of BOP

Question 5

name 6 examples of local delivery devices

Answer 5

1. actisite (EVA fibre with tetracycline)
   - –>clean the tooth, wrap the fibre around neck of tooth and fill it into the pocket. leave for 10 days, then remove.
2. periochip (chlorohexidine in a hydrolsysed gelatine)
   - -> the chlorohexidine in a gelatin chip which over time breaks down, releasing chlorohexidine as it does.
3. dentomycin (micocylcine in a liquid lipid gel)
   - -> fill the pocket with this liquid gel using a syringe. has to be re-applied weeks later.
4. elyzol (metranidazole in a gel)
   - –> gel applied into pocket after scaling and then 2nd time later.
5. atridox (doxycycline gel)
6. arestin (minocycline HCL in encapsulated microspheres)

Question 6

what are the CLINICAL indications when you would use LOCALLY DELIVERED ANTIMICROBIALS?

Answer 6

1. deep pockets greater than 5mm AND BOP
2. would use as an ADJUNCT to mechnical therapy not ‘instead of’
3. would never use it as a first line of response- only for sites NON-RESPONDING after intial therapy
4. the type of device you use is determined by the NUMBER of pockets trying to treat.

Question 7

more long term studies need to be done on local antimicrobials to determine…

Answer 7

1. do they reduce the time/ cost on future dental maintenance
2. do pts. retain their teeth comfortably for longer?
3. is there a reduced need for further treatment/surgery?