Anti-infective Therapy

1
Anti-infective Therapy

• Dr Manal Ahmad Abu Al Ghanam

2
Definitions

• Chemotherapeutic agent acts to reduce the number
  of bacteria present.
• Antibiotic naturally occuring semisynthetic or
  synthetic type of anti-infective agent.
• Antiseptic a chemical antimicrobial agent
  applied topically or subgingivally.

3
Route of administration

• Systemic may be a necessary adjunct in
  controlling bacterial infection.
• Local directly into the pocket has a potential
  to provide greater concentrations.
• A single agent can have a dual mechanism of
  action (tetracyclines)

4
Systemic administration of antibiotics

• 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.

5
Systemic administration of antibiotics

• The treatment of the individual patient is based
  on
• Patients clinical status.
• Nature of colonizing bacteria.
• Ability of the agent to reach the site of
  infection.
• Risks and benefits associated with the proposed
  treatment.

6
Systemic administration of antibiotics

• 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.

7
Tetracyclines

• 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.

8
Tetracyclines

• Bacteriostatic.effective against rapidly
  multiplying bacteria.
• GvegtgtG-ve bacteria.
• Concentration in gingival crevice 2-10 times in
  serum.
• Long term regimens can develop resistant bacteria.

9
Tetracycline HCL

• 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.

10
Minocycline

• 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.

11
Doxycycline

• 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!!

12
Metronidazole

• 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!!!!

13
Metronidazole

• 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).

14
Metronidazole

• 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.

15
Penicillins

• 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).

16
Penicillins

• Amoxicillin is semisynthetic penicillin with
  extended antiinfective spectrum (Gve,G-ve)
• Amoxicillin is for treatment of aggressive
  periodontitis both localized and generalized
  forms.
• Augmentin is used for management of LAP or
  refractory periodontitis.

17
Cephalosporins

• Are not used for treatment of dental disease.
• Patients allergic to penicillin are allergic to
  cephalosporins.

18
Clindamycin

• Effective against anaerobic bacteria with strong
  affinity for osseous tissue.
• For penicillin allergic patients.
• Efficacy to periodontitis refractory to
  tetracycline therapy.
• DOSES150mg (qid) for 10 days.
• 300mg(bid) for 8 days.
• Associated with pseudomembranous colitis.

19
Ciprofloxacin

• 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.

20
Ciprofloxacin

• Side effects metallic taste, inhibit the
  metabolism of theophilline and caffeine, enhance
  the effect of warfarin and other anticoagulants.

21
Macrolids

• 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.

22
Macrolids

• 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!!!

23
SERIAL AND COMBINATION ANTIBIOTIC THERAPY

• 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.

24
SERIAL AND COMBINATION ANTIBIOTIC THERAPY
Bacteriostatic Bactericidal
Erythromycin Penicillin
Tetracycline Cephalosporin
Clindamycin Vancomycin
Metronidazole
25
Guidelines for antibiotics in periodontal therapy

1. Clinical diagnosis and situation dictate the need
   for ABC therapy.
2. Disease activity, measured by continuing
   attachment loss, purulent exudates
3. Patient medical and dental status and current
   medication.
4. Microbiological plaque sampling.
5. Identification of which antibiotics were most
   effective

26
Local Delivery Agents

• Subgingival chlorhexidine .
• Tetracycline containing fiber.
• Subgingival doxycycline.
• Subgingival minocycline.
• Subgingival metronidazole.

27
Subgingival Chlorhexidine

• A resorbable delivery system.
• Biodegradable system that resorbs in 7-10 days.
• No signs of staining were noted in any of the
  studies!!

28
Tetracycline containing Fiber

• 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 !!

29
Subgingival Doxycycline

• A gel system using a syringe with 10 doxycycline
  (Atridox).

30
Subgingival Minocycline

• A locally delivered sustained release form of
  minocycline microspheres (arestin).
• The 2 minocycline is encapsulated into
  bioresorbable microspheres in gel carrier.

31
Subgingival Metronidazole

• 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.

32
Conclusions

• 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.