Anti-infective Therapy
Dr Manal Ahmad Abu Al Ghanam
Definitions
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Chemotherapeutic agent: acts to reduce the number of
bacteria present.
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Antibiotic: naturally occuring semisynthetic or synthetic
type of anti-infective agent.
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Antiseptic: a chemical antimicrobial agent applied
topically or subgingivally.
Route of administration
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Systemic: may be a necessary adjunct in
controlling bacterial infection.
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Local: directly into the pocket has a potential
to provide greater concentrations.
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A single agent can have a dual mechanism of
action (tetracyclines)
Systemic administration of
antibiotics
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1.
2.
3.
4.
5.
Treatment of periodontal disease is based
on infectious nature of the disease.
An ideal antibiotic for use in prevention and
treatment of periodontal disease:
Specific for perio. pathogens.
Allogenic.
Nontoxic.
Substantive.
Inexpensive.
Systemic administration of
antibiotics
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1.
2.
3.
4.
The treatment of the individual patient is
based on:
Patient’s clinical status.
Nature of colonizing bacteria.
Ability of the agent to reach the site of
infection.
Risks and benefits associated with the
proposed treatment.
Systemic administration of
antibiotics
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1.
2.
3.
4.
5.
6.
7.
The clinician is responsible for choosing the
correct antimicrobial agent.
Some adverse reactions include:
Allergic/anaphylactic reactions.
Superinfections of opportunistic bacteria.
Development of resistant bacteria.
Interaction with other medications.
Upset stomach.
Nausea.
Vomiting.
Tetracyclines:
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Used widely in perio.disease treatment.
Used frequently in treatment of refractory
periodontitis and LAP.
Has the ability to concentrate in the
periodontal tissue and inhibit the growth of
Aggregatibacter actinomycetemcomitans.
Exert an anticollagenase effect that can inhibit
bone destruction and may aid bone
regeneration.
Tetracyclines:
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Bacteriostatic….effective against rapidly
multiplying bacteria.
G+ve>>G-ve bacteria.
Concentration in gingival crevice 2-10 times
in serum.
Long term regimens can develop resistant
bacteria.
Tetracycline HCL
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Administration 250mg 4 times daily (qid).
Inexpensive
Side effects: GI disturbances,
photosensitivity, increased blood urea
nitrogen, tooth discoloration when
administered to children up to 12 years.
Minocycline
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Suppresses spirochetes and motile rods.
Given twice daily (bid) facilitating compliance.
Less photosensitivity and renal toxicity.
Side effects: are similar to those of tetracycline
however there is increased incidence in vertigo.
Only tetracycline that can discolor permanently
erupted teeth and gingival tissue when administered
orally.
Doxycycline
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1.
2.
3.
Has same spectrum as minocycline,but only
given once daily(qd) more compliant!!
Most Photosensitizing Agent In
Tetracyclines.
DOSES:
Antiinfective agent; 100mg qd or 50mg bid .
Sub antimicrobial (inhibit collagenase)
20 mg twice daily.
Periostat!!
Metronidazole
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Nitroimidazole compound developed for
protozoal infection.
Bactericidal to anaerobic organisms because
it disrupts the bacterial DNA.
Effective against P.g and P.i but not the drug
of choice against A.a unless combined to
other antibiotics!!!!
Metronidazole
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1.
2.
3.
4.
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1.
2.
Used to treat:
Gingivitis.
Necrotizing ulcerative gingivitis.
Chronic periodontitis.
Aggressive periodontitis.
Doses:
250mg 3 times daily(tid) for a week.
Arestien.(local delivery sustained release form).
Metronidazole
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1.
2.
3.
4.
5.
Side effects:
Antabuse effect when alcohal is ingested.
Inhibits warfarin metabolism.
Patient on anticoagulant should avoid
prothrombin time.
Should be avoided in patients on lithium.
Metallic taste in mouth.
Penicillins
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Most widely used antibiotic.
Inhibit bacterial cell wall production and so
they are bactericidal.
Induce allergic reactions and bacterial
resistance.
Amoxicillin and amoxicillin-clavulanate
potassium (Augmentin).
Penicillins
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Amoxicillin is semisynthetic penicillin with
extended antiinfective spectrum (G+ve,G-ve)
Amoxicillin is for treatment of aggressive
periodontitis both localized and generalized
forms.
Augmentin is used for management of LAP or
refractory periodontitis.
Cephalosporins
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Are not used for treatment of dental disease.
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Patients allergic to penicillin are allergic to
cephalosporins.
Clindamycin
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Effective against anaerobic bacteria with
strong affinity for osseous tissue.
For penicillin allergic patients.
Efficacy to periodontitis refractory to
tetracycline therapy.
DOSES:150mg (qid) for 10 days.
300mg(bid) for 8 days.
Associated with pseudomembranous colitis.
Ciprofloxacin
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A quinolone active against gram negative
rods (all facultative, some anaerobic putative
periodontal pathogens).
Ciprofloxacin therapy may facilitate
establishment of a microflora associated with
periodontal health.
ONLY antibiotic that all strains of A.a are
susceptible.
Ciprofloxacin
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Side effects: metallic taste, inhibit the
metabolism of theophilline and caffeine,
enhance the effect of warfarin and other
anticoagulants.
Macrolids
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Inhibit protien synthesis,bacteriostatic or
bactericidal depending on drug concentration.
Macrolids used in periodontal treatment
include erythromycin,spiramycin,and
azithromycin.
DOSES: Therapeutic doses of 250mg/day for
5 days after an initial loading dose of 500mg.
Macrolids
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DID YOU KNOW….
Erythromycin is not concentrated in GCF,
spiramycin is excreted in high concentration
in saliva and it has been proposed that
azithromycin penetrates fibroblasts and
phagocytes in concentrations 100-200 times
greater than extacellular compartment!!!
SERIAL AND COMBINATION
ANTIBIOTIC THERAPY
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Periodontitis is a mixed infection, in this
condition treatment requires more than one
antibiotic serially or in combination!!!!!
Bacteriostatic drugs require rapidly dividing
microorganisms, they do not function well
with bactericidal antibiotics!!!!
If both types are required then it is best to
use them serially not in combination.
SERIAL AND COMBINATION
ANTIBIOTIC THERAPY
Bacteriostatic
Bactericidal
Erythromycin
Penicillin
Tetracycline
Cephalosporin
Clindamycin
Vancomycin
Metronidazole
Guidelines for antibiotics in
periodontal therapy
1.
2.
3.
4.
5.
Clinical diagnosis and situation dictate the
need for ABC therapy.
Disease activity, measured by continuing
attachment loss, purulent exudates…
Patient medical and dental status and
current medication.
Microbiological plaque sampling.
Identification of which antibiotics were most
effective…
Local Delivery Agents
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Subgingival chlorhexidine .
Tetracycline containing fiber.
Subgingival doxycycline.
Subgingival minocycline.
Subgingival metronidazole.
Subgingival Chlorhexidine
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A resorbable delivery system.
Biodegradable system that resorbs in 7-10
days.
No signs of staining were noted in any of the
studies!!
Tetracycline containing Fiber
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Tetracycline fibers with 12.7mg per 9 inches.
It was well tolerated in oral tissues and
concentrations reach 1300µg/ml
No change in antibiotic resistance to
tetracycline was found !!
Subgingival Doxycycline
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A gel system using a syringe with 10%
doxycycline (Atridox).
Subgingival Minocycline
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A locally delivered sustained release form of
minocycline microspheres (arestin).
The 2% minocycline is encapsulated into
bioresorbable microspheres in gel carrier.
Subgingival Metronidazole
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A topical medication containing an oil based
metronidazole 25% dental gel.
Two 25% gel application at a 1-week interval
have been used.
Bleeding on probing was reduced by 88% of
cases.
Conclusions
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Scaling and root planing are effective in
reducing pocket depths.
When systemic antibiotics are used as
adjuncts to scaling and root planing the
evidence indicate that some antibiotics
provide additional improvement.
There are extensive reviews of the local
delivery agents available for periodontitis.